Android Studio has two particular features that combine to create just a perfect-storm nightmare:

- Every time you make ANY change in a file, it saves automatically (this *cannot* be disabled)
- "Undo" is mapped to CTRL-SHIFT-Z, whereas CTRL-Y is "Delete current line"

So this happens to me *all the time*

- Hit CTRL-Z many times
- Think "Oh... I went too far" or "Oh… I shouldn't have done that"
- Hit CTRL-Y to Redo
- Line deletes
- File *instantly* saves
- Indeterminate amount of work lost