When developing software, it is far too easy to hack something together knowing full well you can do a better job and justifying your actions by saying "meh, I'll fix it later."
We've all been in this situation before (and I'm just as guilty as anyone else) where we have some tests that need written, some code that needs refactoring, or a pattern that needs to be implemented and we trick ourselves into thinking that we will "fix it" later.
Next time you find yourself thinking this way, just stop. Stop and think about what you can do at that moment to make your code better and do it!
Later never comes, do the work now and have something to show for your efforts.