Kurzgesagt on setting goals, routines and habits. Tldr: the more you do something the easier it is to keep on doing it.

My criticism: they didnt address that some activities, in their example, browsing Reddit, might come easier than others like trying to exercise every day. Basically they emphasized individual responsibility, the same way as most similar vids. Reddit has had a lot of engineering put into trying to make it more enticing that healthier activities, so it'll be easier to get into those unhealthy activities since you're basically more predisposed.