There are many reasons people become Uber drivers, such as:
It allows you to be your own boss, working as much or as little as you like. Essentially you start work as soon as you log into the app.
These flexible hours allow you to do it full time or even part time as a supplemental income.
An excellent job for sociable people, and it will enable you to be your own boss.
Because passengers are rated as well, it allows you to avoid passengers who might cause you trouble.