Not all bad jobs are bad because of price. There are the never ins, the no moneys, the quibblers and the never good enoughs, then there's poor access, no parking and dog poo to take into consideration. Some you just want to get rid of because you don't like them.
However, its hard to drop one house if you do a half a dozen others in the same street.
Its a wonderful pont to get to when you have more work than you need.