My wife is a smart lady. Not particularly interested in technology, but no luddite either. She recently signed up with Google Drive so that pictures and videos of our kids could be backed up online.
Files mysteriously go missing from our home computer's LOCAL folders (i.e. the folder of images and videos she wants to sync). In fact many of the local folders were empty! Some have strange duplicates (for example, a "Pictures" and a "Pictures(1)" folder). This was quite a shock when she first discovered it -- "Google Drive is deleting the precious files I want to backup!!!". Looking into it, we discovered that other people have had the same problem.
We were able to find some of our 'missing' files in the "Trash" on our local PC. This caused us even more alarm, because we still lost a lot of really precious stuff from our local computer. So what this meant for us is that while we were able to go to Trash and recover some of the files, we lost many of them. My wife also assured me she wasn't doing anything strange like moving stuff around and deleting stuff while trying to back it up.
This seems really bizarre behaviour for a cloud storage solution. It should never delete stuff from your local computer for you. Or perhaps there are a few cases where it should (if you have manually deleted those items on another computer that syncs with your drive account), but if it does, it should be really careful about it. My wife didn't do anything to suggest to Google Drive that it should delete those items.
Note that I am a big user of Google products, and I'm generally pretty disposed to liking Google: my work uses gmail for corporate email, I use it for my personal email, share videos via youtube, and so on. Heck this blog is run by Google. But Drive has been a massive headache for us.
Thinking of using Google Drive? Just dont do it.