"What factors do you think are influencing your desire to eat more or less?"
There is a lipostat or setpoint in the hypothalamus. It acts like a thermostat for fat. Fat levels are controlled by a homeostatic system, just like body temperature. The highest amount of bodyfat you've had will typically be the bodyfat your brain will defend. It not only does this by making you hungry, it also will downregulate your metabolism. So you become less active. Anyone who has been obese, is fighting their own brain to maintain fat loss. Losing fat is easier than maintaining fat loss. Semaglutide disrupts this system.
BTW, the mechanism of the setpoint is Leptin, a hormone secreted by fat almost exclusively. Muscle also releases Leptin, but in small amounts.
So if you cut the fat out, if you use liposuction, or you diet down slowly, or you diet down quickly, it doesn't matter. Your brain still knows how much fat you have, based on the leptin signals it gets. You cannot trick it.
The reason bariatric surgery is effective is that cutting out the stomach reduces the amount of ghrelin released, which is a hunger hormone that the brain sends the body. Again, disrupting the homeostatic system...which is the only effective way out of this mess.
I was expecting more people on hacker news to know about homeostasis of fat by now. Leptin was discovered 27 years ago.