Let the user know what is happening especially when they cannot interact with the software. Here are some rules we should work to follow.
- *Always give feedback to a user action within 100 ms.- *Always show a busy cursor if something will take longer than 400 ms.- *Always run async and show progress if action will take longer than 1 s.- *Always show time to completion estimate if action will take longer than 10 s.
== Recovery from Mistakes ==