Nothing special just flavor, strength and the consistency of those qualities. The best I've determined is from someone whose job requires them to make coffee bu

Nothing special just flavor, strength and the consistency of those qualities. The best I've determined is from someone whose job requires them to make coffee but also basically to drink it as well. E.g. the overnight gas station attendant and diner waitresses. They want to make good coffee because they will also be drinking it. Of course you can find someone who fits that description and their taste buds are completely shot out or they just have very different preferences too, so compatibility matters.