Personally I think the weight loss comes about because on LCHF you just eat less because you aren't hungry. I have never counted calories just reduced carbs as much as possible.
I agree that is how LCHF works for some people to lose weight without counting calories - because, ultimately, losing weight comes about because you eat fewer calories than your body needs. If you eat less because you aren't hungry, that will create the calorie deficit needed to lose weight.
For good or bad, I don't have the normal hunger triggers - I actually don't know what "hungry" feels like. Some forms of fat trigger cravings for me (which are unrelated to hunger). The absence of grain based carbs triggers cravings for me (so the entire premise of the diet, for me, is a recipe for out-of-control eating (I've been eating LC, moderate protein wtih a 1200 cap (mostly) for more than 11 months, have lost 70 lbs, and have my diabetes under control - so enough experience to know that that that craving isn't just something I'll adjust to over time.). Something in Quest bars does, as well - although I have not narrowed down the specific ingredient, since I only recently discovered Quest bars when I was looking for a small treat at one of our rest stops on a recent road trip.
So I have to count calories (or devise other schemes that result in eating fewer calories) - and be very careful about the kind of fats I'm eating to avoid triggering binge eating. So far, the minor binges have been limited to low carb foods - so it hasn't impaired my BG, but I could easily eat several thousand calories of Quest bars, bacon, or cheese, for example, without batting an eyelash - even though I'm quite happy on (currently) 800 calories a day - as long as I avoid the things that trigger cravigns.
Others take HF as a license to gorge on fat, thinking that LCHF is some kind of magic that defies the laws of physics. If you're on a LCHF diet and not losing weight, because you've been enjoying the HF too much, you may need to count calories - if weight loss is a goal of yours.