You're correct, it's easier for an employee to be fired than for him to quit or resign. He quits if he's fed up with the job and can't endure any longer. I know many people that quit their offline jobs due to bad work ethics.I know most people quit when the job is not so favourable to them. Maybe the work is too much for a little pay, or the boss is too bossy or fellow workers are not tolerable. Anyway, several people have their own reasons for quitting, others can just be a better opportunity has come up.