I replace my brake lights approx every 6 months. Why do they keep going out?

What is your question?

I'll replace the driver's side, then a couple months later, the passenger side, then 6 months later, the driver's side again. It's never ending. I've had the car for 12 years and it seems lately the problem is getting worse. I only drive this car about 3000 miles per year, so it can't be over-use. I've used different brands of lights. No difference. Has anyone else had this problem or know why it's happening? Thank you.