I have a friend who insists on wearing clothes that are neither age-appropriate, nor do they fit half the time. (She believes in the tighter is better concept.) When we go shopping and she tries on something that I wouldn't be caught dead in, I know by the way she presents (prances) how badly she wants it. Her "what do you think?" really doesn't matter because in her mind's eye she looks beautiful - despite the gigantic mirror in the dressing room that screams "my eyes! my eyes!"
In fabric selection, I may be more direct but I try very hard to qualify my statements. I have allowed myself to be talked out of or into fabric because of someone's personal taste. One person's ugly is another's Mona Lisa.