There's this Psychologist named Elizabeth Esther who posted in her blog something very interesting about why people join. Here's her list of reasons (I agree with her take; this is from her blog):
1. We Have What You've Been Looking For: Do you crave meaningful relationships? Are you tired of superficial pursuits? Do you long for abundance, happiness and wealth?
2. Sense of Urgency: TODAY is the day of salvation! What if you die tomorrow? Will you have ANY regrets???? [SIDEBAR: when I was "witnessing" to people, I would get super frustrated when they replied, "Well, if I die tomorrow then I'll be glad I lived a good life." I was like: Nooooooo! BE ANXIOUS! BE VERY AFRAID! Otherwise this whole formula doesn't WORRRK!"]
3. Sense of Purpose: Did you know God has a Great Plan for your life? Do you really want to miss out on that? Join our cause. God is REALLY MOVING in our generation. Together, we can change the world. [SIDEBAR: this whole phrase about "God IS MOVING in our generation!!" really annoys me. Newsflash, guys. God has moved in EVERY generation. God didn't suddenly start MOVING once evangelicals figured out how to build mega-churches. Or win political elections. When I was growing up we were all: yeah, Christianity existed and everything. But it didn't really START until like the 1500's when Martin Luther nailed a letter to a church door. I mean, THAT'S when God REALLY started moving!"]
4. Sense of Superiority: we are the TRUE believers. We are the PURE ones. We are reclaiming what's been lost. We have uncovered hidden truths. You won't find this anywhere else. You might be a nobody in this world, but in OUR group you'll be special. [SIDEBAR: I often call this "The Special-Ness Syndrome." The more SPECIAL a church thinks it is, the faster I run away.]
5. INCENTIVES!!! Look at all these beautiful women following Jesus! Look at all these godly, spiritual men! You could have TRUE intimacy. No more broken hearts. You will find a wife who respects and serves you. You will find a husband who loves and provides for you. You will find a community of like-minded people who will help you and you will never be alone again!! [SIDEBAR: in cults--as in everywhere else--sex sells.]