[OT] Programming practice question

Suppose you're programming some system. You have to reach a milestone
tomorrow.

Your code is kind of messy right now. You can reach the milestone on
time if you write more messy code.

But you'd save time in the long run if you stepped back, reviewed your
code, and reorganized it in a cleaner fashion first. But you don't
have time to do that now, due to tomorrow's deadline.

What do you do?