Let's say there is a situation where you have a knifemaker and a customer. The customer is adamant about wanting something done a particular way and the knifemaker thinks it's really not a good idea and maybe a terrible idea. From the customer's perspective, do you want the knifemaker to save you from yourself or do you just want what you want and that's that? From the knifemaker's perspective, are you gonna refuse to make the knife knowing that your name is on this knife of questionable design for years and years, etc or are you just going to take the cash and move on?
I've personally screwed up in the design department once. It might have been nice to have someone tell me my idea sucked, lol.