to be honest, from a fat black woman's perspective ( cause ya'll never been in my shoes to even talk about this topic):
It begins with the food. It's impossible to lose weight by consuming 3500+ calories per day with 30mins -1 hour worth of exercising.
It boils down to food consumption, understanding how the calories I was consuming was really affecting my body, learning the true meaning of "High-fructose", learning how to really "count calories", properly understanding food portions and weighing food by the ounce, learning to live life without liquid crack aka soda, adapting to enjoy the tastes of vegetables and other greens, and truly noticing that I am less hungry and more fulfilled by living a healthier lifestyle which include exercising (which is why I invested in myself a 2 year 24 hour membership fully paid).
It's been a long way from where I was as a person a 1 1/2 years ago and it truly boils down to the motivation within the person with the willingness to expect failure/success in the new road to change.
I am not to far from my personal/doctor's goal and I am striving to continue my success on my lifestyle change.
Because everyone fails on a diet due to that it is not a true commitment to yourself to fully change your ways.