I make it pretty until I hit a deadline or the customer runs out of money :D

It depends on the customer and project which parts I focus on making "pretty". If it's a data-intensive thing, I might spend time optimising the protocol, compression and making the data pipeline robust. For a web app I'll spend more time making it more usable by streamlining the most relevant flows (which I know of since the client has been testing the (M)VP already).