The way I see it is it is a very long term, likely forever treatment, except if you are not obese to start with. There are a lot less long term reta studies yet, but sema and tirz both have amazingly beneficial long term effects, and these almost certainly will apply to reta, so staying on it is not bad for you, it will reduce the odds of diabetes, high blood pressure, high cholesterol, cardiovascular disease, strokes, cancers, maybe even dementia, and in general the more obese, older and less generally healthy you are the more significant these effects are. There is even some evidence from epigenetic aging marker studies that they slow the aging process itself down.
So assuming you are overweight with any health issues or obese , staying on it is good for you, and if at high risk staying on high doses is better than low doses. Apart from those reasons, ideally with reta or any GLP you really only need to lose the weight one last time, and then just stay on it to keep the weight off, it is almost really that simple. Most people who stop GLP's after losing weight will regain the weight. Some people seem to want to use lower maintenance doses, which is a good idea if there are side effects or you are not at high risk of diabetes or heart disease, and some people do keep the weight off on lower doses. But at the more severe end of obesity there are very good reasons to stay on full doses long term or permanently, if side effects are not a problem.
If the extra weight is short term or situational, like extra kilos after an injury where you could not exercise for a long time, and you lose the weight and re-establish very healthy eating patterns and exercise patterns that you succeed in integrating into your life as well established habits, and do not have to consciously control how much you eat to not regain weight, then you may not need to stay on them, but as far as I can tell this is genuinely rare. For most people obesity is a very long term problem.
