Once a work is out there, it doesn’t really matter what the excuses were. It doesn’t matter if you didn’t have enough time or if the client was an idiot. The only thing that counts is what you’ve designed, and whether it’s good or bad.
Massimo Vignelli, quoted by Michael Beirut in Debbie Millman’s “How to Think Like a Great Graphic Designer”. Which is good to remember when you are creating the conditions for making work and why you shouldn’t take cash cow work.