Headlight burns out quickly on 2005 Land Rover LR3

I've been switching out my headlights now once per month. What's causing them to burn out so fast?

Asked by for the 2005 Land Rover LR3
Is there water getting into the headlight assembly? When you change the bulb do not touch the glass of the bulb the saly in our skin shortens bulb life. Look at the electrical connection at the bulb socket it may be offering high resistance.