A file can appear in your Drive without belonging to you. Before cleaning up, check its owner and location. Removing another person’s shared file from your view is different from permanently deleting a file you own.
Separate two situations
For a file owned by someone else, Remove or Remove from view hides it from your list; other people retain access. Shared-with-you files do not count toward your own storage quota. Opening one again can make it reappear, and removed items can still appear in search.
For a file you own, moving it to Trash does not immediately reclaim its storage. Google says collaborators can retain access until permanent deletion. Trash items are normally deleted permanently after 30 days; do not use Trash as an access-revocation mechanism or a long-term archive.
Check before irreversible deletion
Use a disposable sample to understand the controls, not a team’s only document. Before deleting an owned file permanently, confirm who still needs it and whether ownership should be transferred. Check shared-drive rules separately: this personal-Drive distinction does not describe every organizational permission model.