I spent 2 months working with my first franchisee to ensure he was up to scratch and familiar with the 2 monthly customers, before letting him loose on his own. Not had one complaint in 4 months and all bar one of his checkatrade cards have come back 10/10 the other scoring 9.5.
Like has been said, if it's a persistent problem, he's not competent and needs retraining or has very little pride in his work which would potentially lead to him losing the work to someone else (another franchisee or me). If it was a major problem I'd seriously consider taking action to terminate the agreement, as he'd eventually ruin the reputation I've worked hard to build.