Answer by Ruchira Bhawnani:
Imagine a scenario where in a town there are only two barbers
Their Hair Cutting Shops face each other, and you have to choose one of them for a haircut..
Don't choose the barber with the "better" haircut.
A Barber has to go to another one to get a haircut.
Doctors have to go to other doctors for an operation.
Gynecologists have to go to others for a C-Section.
A Photographer has to hire another for his/her wedding
A dentist has to go to another for a tooth extraction.
A Masseuse hires another for a back-rub.
A vegetable vendor cannot sell veggies to himself, oh well he doesn't have to!
Papa doesn't get a piggie-back ride, he's had his share though in the past..
Big Brother gets watched by Big.. who?
A guard at the Morgue cannot guard his own dead-body.. or may be he can.. I don't know!