- User deletes important doc by accident.
- User's cousin (casual user) comes to visit for a few days.
- User's cousin wants to use Users's mac to check his email.
- User's cousin downloads a personal email attachment while doing this.
- User's cousin wants to really delete the email attachment when finished - only one way he knows how...
- Later... User cannot find that important doc he accidentally deleted.
I think it is a glaring omission that one of the best operating systems around has no user friendly way to really delete a file or group of files from the system. Its all or nothing. Its a very basic privacy/security feature - the ability to really delete a file. Its also a very basic operating system feature to have a trash can or recycle bin as mistakes can and will happen.
In OSX there is no user friendly way to have both these features. You have to compromise - you get either lack of privacy/security (some file you don't want around is still on your computer) or no accident protection whatsoever (have to delete the entire trash can when you may not want to).
All easily accounted for by letting the cousin use OSX's guest account feature. Easy to setup, keeps deleted files safe (well as safe as trash).