Here are 5 reasons why students should never (willfully) use Turnitin, Grammarly, or related plagiarism / text checking tools:

1. You give away (for free) your exclusive rights to use the content. In many cases (doesn't apply to Turnitin but to commercial plagiarism or grammar checking tools), by using their software, you agree that the checked content can be used either in public or private. For example, they can use your content to create or test AI tools (normally, they would have to pay a writer or a person to fill out surveys to provide free content).

2. Your content is indefinitely stored on their servers and the right to use your work can be transferred to 3rd parties without your explicit consent.

3. It some cases, you may have included your personal information in the content and then you would not be able to remove it (either because you cannot prove you were the author or you have revoked your rights to your exclusive ownership).

4. All plagiarism testing tools are unreliable. For example, they cannot distinguish between quoted text / references (you may include some quotes in your paper, which will be classified as plagiarism because the software doesn't know the difference between a quote and non-quote).

5. If you are a student and submit your papers to Turnitin or other databases, you will not be able to use, either in full or in part, YOUR own papers for other projects or classes because they will be marked as "plagiarized."