Myself , if a bad job was done I'd tell that someone they did a bad job it being free or otherwise
Mike your saying you would tell someone who did you a favor that he did a bad job? So you wake up one morning and the neighbor shoveled out part of your driveway. But he did a bad job and you had to do 75% of it over. You would tell him he did a bad job? I couldn't do it no way
I would thank him for his effort & then I would polity ask he not do it again , explaining why . If Dean were to make me a XO & I didn't like the work , I feel it's best to tell him . So if he charged me OR gave it to me free that would have no bearing on how I feel , I feel it is my obligation that he knows I was not happy with the XO & then explain my reasoning to Dean in hopes that a solution could be found .
I handle all my interactions this way with everyone (only exception being the mother-in-law's cooking )