I have a 02 kia optima that the battery light came on and we replaced the alternator and it started running again but the alternator went out again so we replaced it again because I got a used one. I replaced the used one with another used one but this one only lasted about a month. What would make the alternators go out so often I believe it has to be something other than that they just keep wearing out but I could be wrong.
Are you doing the work yourself and are you getting the alternators tested when your bringing them back in the store. When you replace the alternator it is also a good idea to replace the belt too because if the belt is streched the alternator dosent get the rpms needed to keep the battery charged. Also put your battery on a charger for a night so the alternator isnt working with a dead battery which can also burn out an alternator. Good luck : )