Because it sounded cool and a bunch of my friends wanted to do it too.
Honestly, our physics teacher my junior year of high school asked who wanted to build a robot, since FIRST was trying to get more teams in the Richmond, VA area (this was the first season there was a regional at VCU), and a bunch of us agreed and got into it, not realizing what we were getting into. Thus team 422 was born
And I've had the FIRST bug ever since.