JFC why do people persist in not understanding this

"Calories in calories out" is absolutely, necessarily true. It's basic physics. The thing where it can *seem* deceptive is that reality is more complicated than nutrition labels and calorie calculators. Are you weighing your food? Are you actually counting all your activity (this is practically impossible) as it rises and falls? And then what happens inside your body just moment to moment as it metabolizes everything is enormously complicated, pic related and every one of those steps has dozens if not thousands of factors that can impact on it