Last year I discovered a problem with Google Drive, which is documented below:
There are several problems, but the biggest one is that when you're organizing your files (moving them from folder to folder) they may be deleted instead... Not good. If you restore them, their sharing settings may or may not remain intact. Also not good! If you use the service as a cloud backup, you may never even know you (or your clients or organization) have lost things... Double plus not good.
I'm happy to say I'm 40% sure I recovered most of my important files - but with thousands of files, pictures, and settings, how would you ever be sure?
Learn from my mistakes (which technically weren't mistakes) and research.