Love Bombing and the like are recruitment tactics, which is how you get lonely or angry people to look at and engage with the movement. Much the way there's some sound personal advice in Dianetics the point is to get the layperson interested in becoming an initiate. This is one of the cult orgy spots, since yes, some movements encouraged their recruiters to engage sexually with with their marks, not approved by the mainstream since it runs contrary with the anti-free-love themes of Christianity. (Most NRMs by far identify as Christian, though that's its own deep dive.)

(The other cult orgy spot comes in the harems or proclivities of the movement leaders, who often will draw an endless supply of groupies much like athletes, politicians or actors. Or, as per the case of Jim Bakker and Jessica Hahn, can extort attractive workers for sex with low risk of consequence, which seems to run congruous with executive branches of large businesses. The Rajneeshpuram in Wasco County, Oregon, a Tau Buddhist commune is a rare special case for the US, but the local population and the state freaked out not because too much sex was happening, but because it was insufficiently Christian for the 1980s US.)

Once someone is a novice or a practicing disciple, then the movement needs mechanisms to get them willing to labor long hours on cheap food and minimal medical care (sometimes dealing with supply scarcity and disease), and that's when the promise of a big payoff soon comes.

In the cases of MLMs, the promise is you'll get rich too when you are selling AMWAY products to customers, or the next iteration of resellers down the line. This is why doomsdays are popular among NRMs, which have to be imminent. This year. Preferably a month away. Then they know they only have to work a few weeks until the rapture, and it will all be worth it. It's also why the doomsday cult story doesn't end but gets really scary after the doomsday comes and goes without any exciting events. A friend of mine was an AMWAY seller for some time, and had a regular buddy that would show up in a super-fancy suit to come and coach her on selling. In retrospect, it was pretty creepy.

Then the movement's prognosticators may reschedule the apocalypse, usually justifying it with a misreading or new information or whatever, but their service force gets increasingly restless with each one, and something needs to happen. This is the point when special God's Chosen mischief squads are deployed to engage in terrorism, or assassinate government officials or whatever, and if they don't already have the attention of law enforcement, they're now regarded as a clear and present danger. Stand offs and mass suicides follow.

The Millerite Great Disappointment when the second advent failed to manifest between 1831 and 1844 enshrines into US history that life goes on and that your flock of loyal followers get disillusioned and restless if the show fails to start at the designated time, too many times. Thankfully, mass suicides are rare, but it means we can't yet trace a consistent path from the cult building intentional communities and giant statues to when they're shooting at officials and drinking the flavor-aid.