If I know the business of mine much then I considered that as a right business, well it should. No way I will choose business which I don't have any knowledge since it will just wreck me in the long run even I saw others getting profits in the said business.

If profits are well maintained and operations are always successful in majority of the given report time at regular basis then who will say that Im not in the right business. If on cases that it's really avoidable to face the risk of having business which you aren't familiar, then make a way to make it a "right business" and erase all doubts as a single day is important in every business.