As a revert (I stopped practicing as a teen), I returned because I was invited to Mass my first semester of college (I think it was the Solemnity of the Immaculate Conception). It was a very short service because there were so few people in attendance, but it was a nice re-introduction to church. I was invited afterwards to a Taize event that was taking place later that night, and in the meantime, I began reading from the KJV Bible I had brought along. I didn’t get very far, but I got farther than I ever had before.
I didn’t have access to many resources at that point. I figured all branches of Christianity were pretty equal. Around a month later, I found Catholic Answers. Until then, (for example) I had no idea what the Real Presence was, let alone believe in it. Whenever I “discovered” a “new” Catholic doctrine, I immediately believed it. I had been raised (mostly) Catholic, so it made sense to adopt the Catholic beliefs. Luckily, my acceptance of Catholic doctrine grew from accepting it by little more than blind obedience to recognizing that our beliefs and Church itself date all the way back to Jesus Himself. It’s for this reason that I remain Catholic.