Slimming world does work. Temporarily. It also creates disordered eating, creating far more problems long term than you had before. I lost 6 stone on slimming world in less than a year because I’m very good at following rules. All of that is back on now. Plus more.
It’s a pyramid scheme. Leaders actually make very little money and are body shamed into losing weight. My consultant had great membership numbers but would always be told she wasn’t meeting her weight target. She’d lost weight previously on SW (several times actually) but then put it back on. They are told to flog the SW merchandise - magazines, high fi bars, slimming world meals at Iceland. They have to calibrate their scales, but flyers to drop through letterboxes to drum up more business. And rewarded with holidays and little awards if they’ve kept in their weight range and sales range.
Something that demonises mashed up bananas and avocado but you can eat as many of their own ready meals as you like is not healthy eating. Or encouraging people not to eat on weigh day, then binge when they get home, which was common in my group. I was continuing to lose weight by exceeding my syn allowance through eating avocado, nuts, seeds, honey. And some chocolate. There is a complete lack of knowledge about how weight loss works, with the same old shit about muscle weighing more than fat. 1lb of fat weighs the same as 1lb of muscle but muscle is leaner so has less volume - you look thinner if you replace the fat with muscle but you can still weigh the same. Yet constantly the muscle weighs more than fat was trotted out, making people scared to go to the gym. No acknowledgement at all that weight includes water and so your weight will naturally vary through the month as you will hold more water at certain times in your cycle. Given its member base is predominantly women it really should know this. It probably does but doesn’t share it. Instead it works on praising you when you have a big “loss” and making you reflect what you did wrong to have a “gain”. If someone had a big gain, the consultant would blame a night out or a birthday meal out. One meal doesn’t cause a big gain. Restricting your eating and then cracking and binge eating does cause a big gain.
To answer your question OP, they promise you weight loss like I achieved. So they have a lot of hopeful people clinging to them. These people will have some good loses, maybe even made it to target but they’ll have seen someone in group lose loads and make it to target so even if they don’t personally manage it they’ll have seen someone firsthand and cling to that, hoping it could be them. They ignore all the negative aspects like people making fucking desserts out of weetabix or being told to go easy on holiday, not to enjoy themselves because it’ll undo all the progress they’ve made. When actually they restrict so much on holiday and don’t see a loss, or big enough loss, and are distraught and go out and binge. SW promises people who fee shit about themselves an answer, a hopeful future. It develops a mentality of needing each other to lose weight under the guise of sharing recipes and supporting each other but actually you’re just creating an environment that normalises disordered eating. You’re told that the more involved you are the better your weight loss will be. The social team are often rewarded with free membership but they continue to do it because being more involved will guarantee them more success.