Well for me it hasn't always been that way, sometimes when I rest or try to do something else I get carried away.
I think I get frustrated easily and quickly expecting the things I do to pay-off even when I'm not putting in enough work.
And that makes it hard to form a good routine of consistency.
Solving this issue to me only boils down to my mentality. I need to work on the way I think, practice go habits and apply discipline.
(Deep breath)
Deluding yourself that a lack of effort is going into return good rewards will get you nowhere, and getting frustrated won't either. Try ownership, responsibility, discipline and hard work.