When it comes to work, we usually think of two contexts: Working for yourself; and working for another.
In reality, the proper motivation is to work for yourself at all times. The premise of work is that the activity is productive for you. “Productive” means that your life is better off for having done the work, than not. Your motivation can range from working for a modest hourly wage that you nevertheless need; to working for lots of money in a career you find exciting, rewarding and fulfilling; to everything in between. In all cases, you are–or at least should be–working for yourself.
I recognize that there’s a distinction between owning your own business or operation rather than working in another’s. There are great advantages to working in your own operation, as well as added responsibilities. You might or might not be capable of these added responsibilities and, whether you are capable or not, the extra burdens might or might not be worth it to you. All of these are valid factors to weigh and consider, when working. But no matter what the context, you ought to be working for your own sake, most of all.