He needs to turn this into a positive narrative. The Germans have an aphorism: "Stubbornness is the energy of fools." He should reframe this as a persevering focus on his prospect's needs. Sam Walton suggested an approach Rand might consider in his ten rules for building a successful business:
Rule 10: Swim upstream. Go the other way. Ignore the conventional wisdom.
If everybody else is doing it one way, there’s a good chance you can find
your niche by going in exactly the opposite direction. But be prepared for
a lot of folks to wave you down and tell you you’re headed the wrong way.
I guess in all my years, what I heard more often than anything was: a town
of less than 50,000 population cannot support a discount store for very long.
My dad said something similar when I was starting out. He apologizes for it at least once a year. (I totally don't hold it against him, don't worry.)
While I generally don't let People Are Wrong On The Internet get to me, I have one exception: I am by nature a curmudgeon and keep a list in a notebook of predictions along the lines of "You will never sell X of this software." It is eleven lines long at the moment, and has eight smiley face stickers.
I think I'm getting another sticker for Christmas.
I've got a rule that "If it's not impossible, it's not worth doing." If most people think that what you're doing is impossible, you've got less competition.