How many years do you usually use eyeshadow?

It seems like the people around me use a wide variety of eyeshadows.
I was just fascinated lol. There are so many palettes, too...
How many years does it take you to finish an eyeshadow palette?
I have been using 6 different colors for 4 years now without a single puncture.
The color came out well... lol I'm curious