I think most scientists and inventors are simply extremely curious people. There is an overpowering drive to know and understand how things work. And then to take knowledge to the next level and create something with that knowledge. Perhaps a mathematical formula, perhaps a lightbulb, perhaps a television show.
A similar concept can be said of musicians or artists. The drive to create something artistic is overwhelming.
And many have lost their work/life balance in the process, I am sure. The pull is strong.