I believe this practice should stop.

Z-Library should welcome books and documents in different formats. Some materials are extremely difficult to obtain, and text versions created through OCR, manual conversion, or other methods may still have significant value. They may contain formatting errors or imperfect text, but in many cases, having an imperfect version is better than having no accessible version at all.
Whether a particular file is useful, low-quality, or “trash” should be judged by individual readers. Personal opinions should not be inserted into the book title itself, because doing so pollutes the catalog, makes searches less accurate, and presents a subjective judgment as though it were part of the book’s official title.
When users discover serious OCR errors, missing pages, poor formatting, or other quality problems, they should describe those issues in the comments or reviews. This would provide readers with useful information while preserving the accuracy and neutrality of the book title.
At present, the person responsible appears to have altered the titles of more than 500 books. I hope the Z-Library team can identify these changes and remove the added labels in bulk, rather than requiring users to correct the titles one by one. I also hope the administrators can determine which account made these edits and apply appropriate restrictions to prevent similar large-scale catalog vandalism from happening again.
Please keep titles factual and leave quality assessments to the comment section and to the readers themselves.