Duh!  That’s obvious.  You take in and hopefully make money from a business, but you don’t with a hobby.
True, but there are other differences, too.

You have to stick to a schedule and meet deadlines.
You often make items to other people’s specifications  rather than yours.
Your production now may become  monotonous because you make the same item over and over, as I did when producing children’s appliquéd vests.
You may work more hours than you did at your job and don’t make any more money.
You must take care of your own social security and taxes from your profits.
You often encounter customers who are very fussy, …read more