Even if it turns out to be a temporary commitment, you’re still making fun of people who are just trying to better themselves and start the New Year in a positive light.

If someone’s out of shape and you make fun of him for joining a gym at New Years, all you’re doing is disincentivizing them from actually trying to get in shape.

Or if you slate someone who’s trying to be a better person and says “New Year, new me” you’re just disincentivising them from trying to improve themselves.

People should encourage those who try to better themselves at the beginning of the year instead of insulting them, because even if they fail at some point, at least they’re making an effort.