for the last 3yrs i've been changing out my brakelight switch every 5-6 months..what can cause it to fail so fast? i've tried dealers switch and autohaus they both last pretty much the same 5-6months...

Unfortunately it is tough to see in this picture, but the cause of failure on mine was due to breakage of the metal (presumably copper) contact strip. The part moves with each use and probably failed due to fatigue. The screwdriver and pliers point to the small square piece that broke, which is tough to see because of the granite background. That was over 4 years ago, and the replacement is still working fine.