A good friend of mine, who is very successful in life is working on getting fit with her fiancee. She runs a blog and a Facebook page. She asked her trainer what he thought made people give up on goals. He said that it was because "often people don't love themselves enough to keep themselves high on the priority list."
In some cases this may be the case, but I responded to my friend that:
health goals, especially losing weight, the return on investment is
SLOW. You can eat well everyday, drink water, exercise 6 days a week
and you may only lose 1 lb in that week. It can be very frustrating and
make you want to give up. It takes a lot of physical and mental
energy for every pound you lose.
Physical AND mental energy. AND time. The trifecta working against anyone trying to lose weight.
Without one of them, we are pretty much doomed!