but why not and why does he show the level of interest that he does?
He's a man I know in person (not a dating app) and have a couple of interests in common with. Occasionally, not often, maybe once a month or so, I'll see or do something that makes me think of him, relating to one of the interests and send a short chatty message about it.
He always replies quickly, like instantly and we'll chat back and forwards for a while, a bit of banter, some mild flirting. He definitely leaves his replies open for more chat, I'm not forcing it. Then that's that until I weaken and send another one several weeks later.
Once in a while I'll see him at an event and it's all perfectly friendly and fun, but again it will usually be me who says the first hello.
I know I need to stop, but if he's not bothered, why engage at all?