[todwic]

A good mechanik can make bank, while a slow one will starve.

A lot of shops charge work on a fixed scale (a certain job takes X mount of time to do, and you should charge X amount + parts)
so the mechanic gets paid $80 to change an alternator whether it takes im an hour or 10 hours. If he changes 4 alternators in an hour, he gets $320. Write Bosch on the side of that alternator and he gets $210 to change the alternator...