I do believe that people want to change, but they have to want it more than the comfortable (yet unfulfilling) lifestyle and habits that they currently have in order to actually be motivated to put in the necessary effort to change. I think that many people may be unwilling to make changes (despite wanting to improve their lives) because change can be scary---you don't know for sure how things will turn out when you make those first steps (after all, what if things don't turn out as you hoped and experience failure instead?), and if undesirable outcomes happen without the comforts of their old habits to turn back to (the bad habits they are trying to stop), it would all seem like a wasted effort along with unnecessary bad outcomes (ex. rejection, embarrassment, other "failures"). So in general it's probably fear of unknown outcomes that prevents people from actually changing, because there's the feeling that giving up their old comforting ways (which prevent them from making important changes and improvements) may just count as extra "loss" in their lives, since they'd no longer be able to fall back on it in case of failure.
Sorry, that is one lengthy explanation I made :S