My go-to phrase now is that exercise can't help, diet can't help. Neither do any good unless you have both. That was certainly the case for me. No attempt at any diet did any good for me at all, but when I worked on eating better (not dieting, just eating more carefully and limiting fatty food) and threw in regular strong exercise I got results. In my mind, to my experience, it really is a lot of work to lose weight. It's not fast and it's not easy and frankly if I was still working long hours coming home tired after work, I'm not sure I could have done it so I don't begrudge anyone's lack of success. It took retirement and a lot of work in my case.