A true professional does not waste the time and money of other people by handing over software that is not reasonably free of obvious bugs; that has not undergone minimal unit testing; that does not meet the specifications and requirements; that is gold-plated with unnecessary features; or that looks like junk.
Take reasonable steps to test, document, and otherwise draw attention to the assumptions made in every module and routine.
Value clarity equally with correctness. Utilize the proven techniques that will produce clarity in your code. Correctness will likely follow suit.