Lots more than "98%" of people manage to follow the proper regimen. Hell, there are ENTIRE COUNTRIES where obesity isn't even close to being a serious pandemic problem like it is in western countries.
The problem is the people you're looking at have willpower issues to begin with. That's WHY they have weight problems in the first place. Sticking to a diet/exercise regimen is understandably hard for some people, but if you don't stick to it and then make no progress you have nobody but yourself to blame.
It blows my mind that your post is modded "insightful". It really should be -5, Ignorant as fuck.