Top 10 Cons & Disadvantages of Using Grammarly

Professional writing has moved far beyond simple spell-checking. Modern communication now relies on writing enhancement tools and artificial intelligence to refine tone, ensure clarity, and even generate entire drafts with a single click. As the dominant player in this space, Grammarly continues to lead with innovative features that promise to make every user a better communicator. However, this technological shift also brings significant new challenges.

Table of Contents

Despite its market dominance, the latest updates to Grammarly have introduced a unique set of drawbacks that users and enterprises are only beginning to navigate. From “AI hallucinations” in its generative features to the narrowing of creative voice through over-standardization, the platform’s disadvantages are becoming as prominent as its benefits. This article offers a critical and updated look at the top ten drawbacks of using Grammarly in today’s high-stakes digital environment.

What You Should Know About Grammarly

Grammarly has evolved from a simple grammar checker into a system-wide AI writing layer embedded across browsers, desktop apps, and mobile keyboards. It no longer just fixes mistakes—it interprets intent, rewrites paragraphs, and reshapes messaging based on tone, audience, and brand rules. This power can dramatically improve productivity, but it also means Grammarly now processes more data, makes more assumptions, and exerts greater influence over how people write. Understanding Grammarly today requires seeing it for what it is: a highly capable assistant that can either sharpen your work or quietly flatten it. Without deliberate human oversight, users risk trading clarity for conformity, speed for accuracy, and convenience for control.

Main Features

Real-Time AI Proofreading: Instantly flags grammar, punctuation, clarity, and complex sentence structure issues.
Generative AI (Grammarly Go): Drafts emails, documents, and summaries based on short prompts and context.
Strategic Tone Transformation: Rewrites content to sound formal, casual, confident, or diplomatic on demand.
Brand Voice Integration: Enforces custom style guides across teams for consistent corporate communication.
Plagiarism & AI Detection: Scans massive databases to identify originality issues and AI-generated patterns.
Cross-Platform Ecosystem: Runs across browsers, operating systems, mobile keyboards, and desktop applications.

Real-Life Example: A mid-sized SaaS company rolled out Grammarly’s Brand Voice feature across its marketing, support, and sales teams to improve consistency. Within weeks, productivity improved, and fewer edits were needed from managers. However, leadership noticed customer emails and blog content began sounding unusually similar, regardless of department or intent. High-performing writers were asked to “dial back” Grammarly usage so their natural tone and strategic judgment could reassert control—highlighting how the tool works best as a guide, not a replacement for human decision-making.

The Top 10 Drawbacks of Using Grammarly

While Grammarly’s benefits are real, its weaknesses become obvious when used at scale or without skepticism. The tool increasingly prioritizes uniformity, automation, and monetization over nuance and judgment. Below are the ten most significant drawbacks that writers, students, and professionals must consider before blindly accepting every suggestion.

1. Generative AI Hallucinations

The latest Grammarly includes deep generative AI capabilities, which occasionally present false information as an absolute fact. Because the tool is designed to sound confident, it can fabricate citations, dates, or historical events within your drafts. This “hallucination” effect is particularly dangerous because the prose remains grammatically perfect, making it much harder for a tired writer to spot a factual error. These hallucinations typically surface in the following high-risk scenarios:

Fabricated statistics inserted into business reports without verifiable data sources.
Inaccurate historical references introduced into student essays and academic submissions.
Confidently stated but entirely non-existent legal citations presented as authoritative facts.

Real-Life Example: A marketing executive used Grammarly to draft a product launch email, only to find the AI had “invented” a specific safety certification that the product had not yet received. This error was sent to over 5,000 subscribers, forcing a public retraction and causing significant brand damage because the team trusted the AI’s polished, authoritative-sounding tone without verifying the specific technical claims.

2. Homogenization of Creative Voice

Grammarly’s primary goal is to make text clear and concise, which often results in the removal of unique stylistic choices. By strictly adhering to “standard” professional English, the tool frequently flags creative metaphors, intentional sentence fragments, or rhythmic pacing as “errors.” Over time, writers who rely too heavily on its suggestions may find their work sounds increasingly robotic and indistinguishable from everyone else’s. This gradual flattening of voice usually manifests in the following ways:

Loss of unique brand personality through repeated replacement of distinctive phrasing.
Stripping of poetic or narrative devices deemed unconventional or stylistically risky.
Over-reliance on “safe” but boring vocabulary that lacks emotional or tonal impact.

Real-Life Example: A novelist trying to use the Grammarly desktop app for a draft found that the tool kept trying to “correct” the dialect of a specific character, ruining the immersion. The software persistently flagged non-standard slang as “incorrect grammar,” and after following the suggestions for one chapter, the author realized the character’s voice had been completely stripped of its cultural and regional charm.

3. Significant Performance Lag

As Grammarly has become more feature-rich, it has also become more resource-intensive. On many systems, especially when working in long documents or complex web interfaces, the extension can cause noticeable typing lag. This “latency” can break a writer’s “flow state,” as the underlines struggle to keep up with high-speed typing, sometimes leading to browser crashes or frozen windows during critical writing tasks. These performance issues commonly appear in the following technical forms:

High RAM and CPU consumption during real-time scanning of large documents.
Stuttering cursors and delayed keystroke responses in long-form writing environments.
Incompatibility with low-spec mobile devices and older desktop hardware setups.

Real-Life Example: A journalist working on a 5,000-word feature found that their browser became unresponsive every time Grammarly tried to re-scan the entire document after a small edit. The lag grew so severe that there was a three-second delay between typing a letter and seeing it appear on screen, eventually leading to a full system crash that resulted in the loss of several paragraphs.

4. The “Free Version” Paywall Barrier

While Grammarly offers a free tier, it has become increasingly aggressive about “locking” the most useful insights behind a high-priced subscription. Users are frequently teased with “Advanced Issues” that the tool identifies but refuses to explain or fix without a Premium upgrade. This can lead to a frustrating experience where the user knows their text is “wrong” but lacks the tools to correct it. This paywall-driven frustration is most evident in the following areas:

Critical style and tone fixes hidden behind an expensive recurring premium subscription.
Plagiarism checking functionality restricted entirely to paid-tier users.
Constant upsell pop-ups interrupting focus during active writing sessions.

Real-Life Example: A student on a budget saw “14 Advanced Issues” in their thesis but couldn’t afford the $12/month fee to see what they actually were before the deadline. They spent three hours trying to guess what the “style” issues might be, only to realize later that the tool was merely flagging common words it considered “overused” rather than actual grammatical errors or critical mistakes.

5. Poor Contextual Awareness in Specialized Fields

Grammarly is an expert in general English but a “newbie” in niche industries like law, medicine, or advanced engineering. It often flags technical jargon or specialized formatting as errors because it doesn’t understand the specific context of the field. This forces professionals to manually “ignore” dozens of suggestions, which defeats the purpose of an automated tool and wastes valuable time during the workday. These contextual failures usually show up in the following professional scenarios:

Incorrect “corrections” applied to legitimate medical terminology and clinical language.
Failure to recognize legally binding “terms of art” used in contracts.
Misunderstanding of complex scientific sentence structures and accepted formatting norms.

Real-Life Example: An attorney found Grammarly constantly trying to change “shall” to “will” in a contract, which would have significantly altered the legal obligations of the document. The attorney had to manually dismiss over 40 suggestions in a single document, creating a tedious workflow that actually took longer than if they had just proofread the entire ten-page legal contract manually from the start.

6. Privacy and Data Security Risks

Because Grammarly operates in the cloud, every word you type is transmitted to its servers for processing. Even with high-level encryption, this remains a significant concern for those handling sensitive corporate secrets. In 2026, as data breaches become more sophisticated, the “always-on” nature of a writing assistant that reads everything you write represents a non-trivial security surface that many IT departments find unacceptable. These security risks become especially concerning in the following situations:

Transmission of sensitive corporate or personal data to external third-party servers.
Potential for metadata collection, behavioral tracking, and long-term data retention.
Direct conflict with strict HIPAA, financial, or government data protection laws.

Real-Life Example: A financial analyst was barred from using the tool because the company’s IT policy forbade any software that “listens” to the contents of confidential internal spreadsheets. The analyst had accidentally left the extension on while drafting a private merger proposal, which triggered an internal security alert since the sensitive data was being uploaded to an external server for grammar analysis without prior authorization.

7. Inaccuracy in Non-English Contexts

Despite its global reach, Grammarly remains strictly focused on English. For multilingual writers, the tool is often a hindrance rather than a help. It cannot check grammar in Spanish, French, or Mandarin, and it frequently gets confused when English text includes foreign phrases or names, often suggesting “corrections” that are actually misspellings of the foreign words it fails to recognize as valid proper nouns. These language limitations typically create problems in the following use cases:

Zero functional support for writing or editing non-English languages.
Erroneous flags triggered by foreign names, phrases, and proper nouns.
Inability to assist with translated, localized, or bilingual content workflows.

Real-Life Example: A bilingual marketing team in Montreal had to disable Grammarly because it kept “correcting” the French portions of their bilingual social media posts into gibberish. Every time they used a common French phrase like “C’est la vie,” the tool suggested changing it to “Sets the view,” causing the team to accidentally post nonsensical captions that confused their local audience and damaged their credibility.

8. Technical Conflicts with Other Apps

Grammarly often struggles to play nice with other software. It frequently conflicts with built-in spellcheckers in apps like Microsoft Word or with other AI tools like Microsoft Copilot. These “software wars” can result in doubled-up underlines, conflicting suggestions, or UI glitches where the Grammarly widget covers up important buttons or menus within the application you are actually trying to use on your desktop. These conflicts most often surface through the following technical annoyances:

UI overlap issues with other productivity tools and floating interface elements.
Conflicts with built-in “Track Changes” and native editing features.
Glitches appearing in specialized editors like WordPress, Scrivener, or CMS dashboards.

Real-Life Example: A blogger found that the Grammarly widget sat directly on top of the “Publish” button in their CMS, making it impossible to click without first disabling the extension. The widget’s floating icon also blocked the scroll bar, forcing the user to refresh the page multiple times just to navigate their own dashboard, which turned a ten-minute posting task into a frustrating forty-minute technical struggle.

9. Over-Correction of Tone (Tone-Policing)

Grammarly’s “Tone Detector” has become increasingly opinionated. While it aims to prevent you from sounding “rude,” it often flags assertive or direct language as being “too aggressive.” For women in business or people in leadership roles, this can feel like “tone-policing,” where the software pressures the user to add “hedging” language (like “I just think”) that actually weakens their overall professional authority. This tone overreach typically affects communication in the following ways:

Softening of necessary, direct communication required for leadership and accountability.
Cultural bias embedded in what the system defines as “polite” language.
Automatic flagging of confident statements as emotionally forceful or aggressive.

Real-Life Example: A project manager felt pressured to change a direct request for a status update because Grammarly flagged it as “demanding,” ultimately leading to a missed deadline. By following the AI’s suggestion to make the email “friendlier” and less urgent, the recipients didn’t realize the request was time-sensitive, resulting in a project delay that cost the firm several thousand dollars in late fees.

10. Dependency and Skill Decay

The most subtle but dangerous con is the long-term impact on a writer’s own skills. By relying on an “auto-fix” for every comma and preposition, users may stop learning the underlying rules of grammar. This dependency means that if the tool is ever unavailable—such as during an offline exam—the writer may find themselves unable to produce high-quality work on their own without digital assistance. Over time, this dependency creates the following skill-related problems:

Gradual atrophy of basic proofreading and grammatical reasoning skills.
Inability to write confidently or accurately without an active internet connection.
A false sense of competence created by constant AI-assisted correction.

Real-Life Example: A student who used Grammarly for four years of college struggled during an in-person, pen-and-paper job assessment because they had forgotten how to punctuate complex sentences manually. Without the red underlines to guide them, they made basic errors in subject-verb agreement and punctuation that they hadn’t actually thought about since high school, ultimately failing to secure the competitive entry-level position.

Conclusion

Grammarly remains a powerful writing assistant, but its strengths come with meaningful trade-offs that should not be ignored. While it excels at improving clarity, correcting surface-level errors, and accelerating routine writing tasks, overreliance can quietly introduce new risks. From factual inaccuracies and creative flattening to privacy concerns and technical friction, the tool’s limitations become more pronounced the deeper it integrates into daily workflows.

Used blindly, Grammarly can weaken judgment and originality; used intentionally, it can support stronger, more efficient communication. The key distinction lies in control. Writers who treat Grammarly as a suggestion engine rather than an authority preserve their voice, accuracy, and skill over time. Ultimately, the most effective writing still depends on human discernment—knowing when to accept a recommendation, when to reject it, and when to trust experience over automation.