Yeah, its true it takes a while, but you have to say that it is more stable and programs don't crash taking your PC with it so often.
The reason it wouldn't work straight away is because the program might still be sorting out through a small process, and sometimes that function won't get at it right away to stop it, though if this happens, just end task again, and wait a few seconds, and do it again and it should work then.
You know it has worked when it comes up with the box saying to end the program.