I think we need more visual cues for common operations to give more assurance and reinforce the action. For example, recently I was trying to back up some photos from an android phone by plugging it into a windows machine and copying files over. I already had an older version copied from before, and I was surprised that the copy action resulted in the same number of files after I selected "skip" in the dialogue. What happened was that I probably tried to copy from windows to android by mistake. With everything looking the same it's easy to miss things and have the wrong mental model of what is about to happen. It would be great to have more feedback for actions like this, maybe show the full paths, show the disk/device icons with a big fat arrow for the copying direction or something. Basically the copy/move dialog is the same for 10 files and 10,000 files, same for copying between devices and within the folder... and it will happily overwrite any files if you click the wrong option by mistake. And unlike trashing files I am not sure it's possible to undo the action.