Why the windshield washer pumps fail for everyone

[xfizzle]

So we have a 2001 X5 and a 2002 325 wagon, in one month four out of five of the washer pumps failed. The dealer brought the first one to our attention when the 325 was in for service and said $140 to fix. I said no thank you. You can get the pumps on eBay for $15 each with free shipping--the ones in the X5 don't even need any tools to replace and is literally a 3 minute job. So afterward I smashed open one of the broken pumps and much to my suspicion I found that it was rusted to all hell. So basically the pumps fail because the seal between the motor and the pump area eventually leaks with age and rusts out the motor and then no more windshield washing fluid goodness. The SA actually told me "washer pump electrode loop was indicating a fault"--I think he tried to scare me away from doing a DIY repair because he knew how easy it would be.