Doing something just because you told yourself you would isn't always good though. Not doing something when you're understandably tired, is not laziness. Laziness is an unwillingness to work or use energy. If you're tired, there's no energy to be unwilling to use. You'd likely be better off using that time to recover. Breaking down tasks is a very helpful approach though, I just question the motivation for using the trick. I would say break down the task and see how it feels when you get to the hard part. You might be feeling good about it by then but you don't have to do it if you still don't feel it. Of course, if it's something you have to do, try to give yourself ample time before it needs to get done.
Doing something just because you told yourself you would isn't always good though. Not doing something when you're understandably tired, is not laziness. Laziness is an unwillingness to work or use energy. If you're tired, there's no energy to be unwilling to use. You'd likely be better off using that time to recover. Breaking down tasks is a very helpful approach though, I just question the motivation for using the trick. I would say break down the task and see how it feels when you get to the hard part. You might be feeling good about it by then but you don't have to do it if you still don't feel it. Of course, if it's something you have to do, try to give yourself ample time before it needs to get done.