The 'suspended' state in UWP apps is a rather good UX implementation. Unfortunately most apps I came across don't use the best practices making the apps stutter coz no onlaunched or onsuspended was defined well. Windows never "shutting down" (unless restarted) means simple shutdown -> switched on doesn't terminate a lot of these apps and their background tasks never ended and everything goes yuck.
As much as I love Windows, they seriously need better Quality Control.