For me (neurotypical as far as I know), habits are a mix of 3 things:
- Conditioning from when I was a kid (quite literally Pavlovian Conditioning) which I will do without thinking. For example I will clean my shoes on the doormat both on the way in and the way out, the latter not really making logical sense: I've just been conditioned by my mother when I was a kid with constant "Clean your shoes!" and the behaviour just got associated with the trigger of going over the doormat, hence I unthinkingly do it also on the way out
- Familiar and always (so far) no problem choices. For example having lunch in pretty much always the same handful of places, buying the same brand of certain things. As an introvert I am not comfortable with new places with new people plus there is a cognitive cost (and risk) with trying new things, hence the familiar feels comfortable and the unfamiliar discomforting. The habit is driven by favoring the easy/comforting over the discomforting. This is not the same as being unable to change: I'm actually a serial immigrant and can very quickly adjust to living in a completelly new place and a different country (nowadays it takes me only a few days) - it's just that there is a huge barrier to actually get myself to the point of starting such a change.
- Stuff I have to force myself to do because it's important to do it for social or health reasons. Shave, proper cooking (rather than quick improvisation involving no significant meal preparation or ready-made meals), even brushing my teeth.
All those things qualify as habits (in the sense of being done regularly) but the drives for each class of thing are very different.
PS: I get the impression that what some think of as habits in a neurotypical sense is mainly the first class of things. As far as I know nobody has only conditioned habits, plus you can't really condition complex things (at best you can have a "get up and go do it" conditioning).