I'm actually compiling a list of UI text mishaps, and I plan to publish it as a blog post at one point. A simple one would be to avoid using "your" in a "user -> UI" context (command), and "my" in a "UI -> user" context (message). For example, "Delete My Files" is okay on a button, but, in a message it must be "Are you sure you want to delete your files?". But, the better is to avoid generous use of "your" and "my" unless necessary to disambiguate.

For example, don't have a button that reads "Go to your profile", that screws up translations in languages like Turkish.