what can cause my starter to go bad everytime? on 1993 Mitsubishi 3000GT

i have gone through about 10 starters and they all seem to go bad over a 4 day period and i dont know what the reason could be to make them go bad. Supposely their are differnt types of starters for my car and their is a certain starter with an "apendix" that will hit my torque converter to make it turn over but we found that one and has only been working for at least 4 days and it wont turn on at all.

Asked by for the 1993 Mitsubishi 3000GT
What is your battery voltage? It must be at least 12.6 volts. If the car won't start, and it is a stick, you may have a bad clutch switch, this allows the starter to engage when you press on the clutch pedal. Or, if it is an automatic trans, you may have a bad neutral safety switch or even a defective ignition switch. Most starters have some form of a bendix drive that enables the starter gear to engage the flywheel on on the torque converter.