What motivates you to pursue science?

I didn't do a whole ton with my PHD before moving to software development where I get paid a ton more.

I keep up with research for fun, but am curious as to what rationales folks have for not doing a much easier job for much more pay.

Surely someone more disciplined than me could make money doing software development (just work 4 hours a day most people in this field are lazy and you can easily match their output if you have the discipline to finish a phd), then pursue the research they want in the rest of their time.

Thoughts?