I agree - in my experience, "motivation" is a wildly volatile concept, especially in how a) when it arrives to your thought process, it's usually in the form of bemoaning a lack of motivation, and semi-consequently b) one almost always thinks about "motivation" in a form that is highly moralized (i.e. inviting shame & co.). I find that usually when we employ "motivation" as a concept, it is usually (whether explicitly or latently) in the context of personal failing.

The most success I've had in actively dealing with things like this is when I am able to frame a situation for myself in an extra-moral way and actually believe it - i.e. that something is, like you said, a matter of habit-building and consistency, rather than ontological and exertional good-enough-ness. The tough part here is that many people understand this, cerebrally, but it takes drilling this perspective quite a lot to actually ingrain it into one's belief system.

There's a night and day difference, though, between "well I guess I couldn't do it after all" and "well I guess that's a one-day blip on a four-day streak", and people with 'motivational' difficulties also aren't that great at conceptualizing about & nurturing incremental progress towards an abstract goal, which this also helps immensely with.

All in all I love that your takeaway was, effectively, that 'motivation' can be seen as behavioral inertia that hasn't yet been solved by habit-training. It's not a poetic nitpick at all; at least in my view it's the fundamental operative basis for dealing with the phenomenon of procrastination.