[in the context of creatively solving a programming problem]

"You will be wrong. You're going to think of better ideas. ... The facts change. ... When the facts change, do not dig in. Do it over again. See if your answer is still valid in light of the new requirements, the new facts. And if it isn't, change your mind, and don't apologize."

-- Rich Hickey

(note that, in context, he tries to differentiate between reasoning with incomplete information, which you don't need to apologize for - just change your mind and move on - and genuine mistakes or errors)