If I love myself just the way I am, then there is no need to make changes. If I want to be someone who improves myself, then I have to not-love some aspects of myself. At least, I have to think that I will love the change even better. The harder the change, the bigger the difference needs to be between how I feel about what I am and how I feel about what I could be. The desire has to match the difficulty.
Losing weight is really, really, hard. And the only way I can do it is if the gap between how much I like what I am and how much I like what I could be is really, really, big. And the only way to widen that gap enough is to hate what I am, to make it so I have to change. Because if there is any other acceptable option, I'd take it. And that's a problem.