I experienced a bad mirror motor in the GS I owned previously so what you say makes good sense. Also, the motor is not line replaceable so the entire mirror/housing which is factory painted has to be ordered. If there is any clear-bra protective film that needs to be done too. Wonder why the motor was not shop replaceable?

 

There was no statistical information, but it was listed as a frequent repair on MSN autos. I noticed on more than one of the pre-owned GS that I looked at that the mirror motor had been replaced (saw it on the CarFax).