What's the point of New Year's Resolutions?

Well, it's that time of the year again. The time when people will be quitting smoking, working out, dieting, etc. in droves. And I really don't understand it. I was never one to make a Resolution, except maybe to quit smoking here and there (but don't they tell you to set a deadline to quit?), so I never really had to worry about breaking them. Two of the most popular Resolutions are to quit smoking and quit swearing. And I enjoy doing both of those things entirely to much to stop doing either of them.
Now to be clear, when I said earlier that I didn't understand making a New Year's Resolution, it's not that I don't get the reasoning. People making promises to make themselves better, I'm cool with that. No, what I don't get is why people wait till January 1st to do whatever is they are trying to do. First of all, if you want to make a New Year's Resolution, you should do so on your date of birth, since that is technically the start your "new year". But more importantly, if you really want to better yourself, you shouldn't wait till it is trendy to do so. You want to quit smoking? Put the butt out right now. You want to lose weight? Drop the fork and get your floppy ass to the gym. There is no better time than right now. If you are truly serious about improving who you are either physically, mentally or spiritually, then you shouldn't set a date on when to start, you should do it immediately. No one knows how long where going to ride this roller coaster of life, and before you actually get around to bettering yourself, it may be too late. The safety bar may come loose and send you flying face first into the horn of a unicorn on the merry-go-round. (But at least you didn't die from smoking!)