Isn't this a bit unfair. You kind of belittle the losing weight, quitting smoking, and exercising, and yet you were thinking of something similar with stop eating sweet food.
Nope. I am no different to other people. However, what I am trying to point out is that when people make their resolution to "lose weight" (which they see as a positive action, they aren't making a sacrifice at that point. If perhaps they said I am going to cut out watch "xyz show" and during that time exercise, that sacrifices something. Does that make sense?
I have quit smoking after being a smoker for well over a decade. It is hard. But, "quitting smoking" isn't a sacrifice, as it is something wanted. The quitting is a gain. Similar with exercising more - it does mean sacrifice in other areas perhaps, but maybe making that sacrifice the focus will increase the chances of spending that time exercising.
The fact is, most people fail at their resolutions, because we easily fall back into their habits. If we give up loved habits, we will feel the loss and maybe look to fill the void with something better.
I guess we have different interpretations of sacrifice. I'll just leave it at that.
Replace those loved but bad habits, with discipline and good habits. I like that.