I am developing a Java Swing application, and I want to improve the UI so it better guides users to increase their probability of success.
When the UI discovers some fields are not filled, some state is not reached etc. a messagebox pops up telling the user. But this is quite blocking their flow, since it takes away the focus from the application and forces the user to read and acknowledge the message box before they can move on.
So I thought about messages popping up on the side, without the need of being acknowledged and without taking keyboard focus or being modal in any way. This would get quite close to Clippy, the office assistant. Probably a lot of people know this assistant, yet I do not know anyone who actually liked Clippy.
What other ways could there be to improve users' experience without annoying them?