Well, this is a very interesting question, indeed...
I would say that for a long time I ASSUMED I would have no interest in any other religion. And yet...still, something was very appealing to me about other people's faith. Especially SOME other people's faith.
Well, I went to NO church or religion for about a decade, tho I have always prayed and just paid attention. Then I started looking into them all, to one extent or another. I spent at least some time in dozens and dozens of different churches.
Somewhere along the way, I thought I had figured out that your experience in a particular church had NOTHING to do with the doctrine and EVERYTHING to do with the individual leader of that individual church, the pastor, or whatever.
Always, I guess, tho I probably didn't realize it for a very long time, I was looking for the 'knowing them by their works' thing.
And it has brought me full circle to Catholicism (which, I might add - unlike long ago and unlike many other Christian churches - is the MOST recognizant and respectful of the spirituality of persons of OTHER Christian faiths).
It seems that, if you're going to be Christian, Catholicism is really what that's about.
I have come to have a great love and appreciation for the beauty of the medals and statues and music and 'aura' that JWs had the gall to denounce as 'evil'.
And, an appreciation for the beauty of the Holidays and all the many wonderful things they have 'borrowed', melded and incorporated from other times and cultures and faiths. To UNDERSTAND their background is to learn a great deal about God and about faith and about Christianity.
I feel 'home' in Catholicism.
But I still (to no criticism from my church, by the way) LOVE to explore the faiths of the world.
And, for people who would like to do that, I very highly recommend Huston Smith's books on religions of the world (he explores all the major ones, in such a way as you can get an idea of what they are all about). Smith has even done a 6-part series on world religions for PBS with Bill Moyers.
He had a very unique background when it comes to religious upbringing and he uses it in the very best way possible.
In the end, I find a real truth in the introductory text of the Catholic Cathechism, which observes that, in every place and through all of time, 'man is a religious being'.
We all recognize God and even gesture to the same places (the sky, or our own hearts) when we speak of Him. No culture has ever existed that had no relation, no connection, no communion with God.
We all do it. And we almost always do it together, in one form or another. When we can find the place where that feels right.
He and 'we' are part of the same stuff.
It is universal.
Presently, I pray and ponder the reality that Christians and Muslims are all praying to the same God.