Well, I would argue that most people follow one religion over another, broadly speaking, because the religion they follow happens to be an influential and widely-accepted faith in the culture in which they were raised. That seems pretty straightforward and obvious, no?
Here in the West most folks identify as Christians, whereas in India most folks identify as Hindu, and that distinction is to a large degree self perpetuating within each culture. No mystery there, although various factors may influence this person or that to gravitate toward a particular flavor of Christianity or Hinduism, as the case may be. And of course cultures evolve, sometimes to incorporate other religious faiths, sometimes to move either toward or away from specific dogmas, or toward or away from secular pluralism, and so on.
I'd also argue that, generally speaking, a person who is inclined to be devout will be devout regardless of the religion he or she professes. And the same basic psychological motivations that drive intensity of faith, let's call it, will apply across time and culture, and hence across religious traditions. Or in some cases even across religious versus non-religious articles of faith, so to speak...
Is that more clear?
Cheers.
