As a computer user, the natural action by turning off some folders for Selective Sync the files on the local machine should have remained intact but DropBox app deletes those files from the local drive. This has cause me lose some very important files I entrusted to DropBox.
Secondly, I happen to upload files to DropBox from other machines and devices, I doubt that I have also lost those files too.
[This thread is now closed by moderators due to inactivity. If you're experiencing a similar behavior, feel free to start a new discussion in the Dropbox Community here.]