Would someone hold a belief knowing it to be inferior?

If someone did think that another faith was better (as opposed to just different) then it might seem likely that such a person would adopt certain of those "better" elements in that "better" faith or else convert to it. It seems unlikely that anyone would continue to hold an "inferior" position once they know that it is inferior.

But is it really unlikely?

What about the person who has too much of a vested interest in an inferior position, such as a person who has professed it for a long time and has their identity wrapped up in this faith? Such a person might continue to profess an inferior faith.

I think people have certain religious needs--certain questions that since childhood beg to be answered.  Once they find an answer (even a weak one), many will stop looking because the search is so hard and so unsettling: every question opens up more possibilities rather than cosing them down.

When faced with contradictory evidence, a person holding what they know to be a weak position (but won't admit it) will most likely deny the evidence, attack or marginalize it, or else witness to themselves (publicly) that they have privileged information.

While it is certainly possible for them to go back to the drawing board and reconsider everything. This is extremely difficult and unsettling. Hence, most would rather live knowing that there are holes in their understanding that are better left alone. They even give these holes names such as "mysteries." They exalt those who can live with such mysteries as "faithful."

To profess a faith that you know to be flawed is to be a hypocrite. I dare say that hypocrites are the religious majority. If I am right about this, then most people think they have a inferior position. They just don't have the courage of intellect to question their fundamental assumptions in slim hopes of finding something better.

You don't open Pandora's box unless you are quite sure that you can close it again, and from what I know about that box it may not be possible to ever close it again.

Hence, better to hold an inferior view than to lose what tenuous grasp of things unseen that you have.