Why does he keep reaching out if he's not interested?

Look at what he does across weeks, not what he says in one message. If he texts often but never suggests meeting, never asks you anything specific, and only reaches out when it is late or when he has nothing else on, that is a clear shape. The messages are cheap and so is the effort behind them. A person who wants you will usually pick a day, name a place, or ask about something you said last time, even when he is nervous about it.

Pay attention to what his messages are about. If they are all about his own day, or they are short and easy to ignore, he is keeping the thread warm. If he remembers small details and follows up on them, the interest is more real even if he has not asked you out yet. A single mixed signal means little. A repeated one means a lot.

Also notice how he responds when you pull back a little. People who are invested tend to notice and adjust. People who are keeping options open often just let the thread fade without any drama.

The clearest test is to make a concrete ask. Propose a particular day, a specific place, or a plan with a clear yes or no at the end. Keep it casual so it does not feel like an ultimatum. What matters is that he has to choose. If he says yes and follows through, you have your answer in the good direction. If he dodges with something like let's see or maybe, or answers with another open-ended message, he has told you he is not willing to put anything real on the table.

Don't pad the ask with apologies or extra reasons. A plain suggestion is easier to respond to honestly. Give him room to say no without any drama, and do not follow up with a second, more pleading message if he ignores it. One clear ask is enough to learn something.

Once you have made a clear ask and he has dodged it, you have enough information. Continuing to answer his casual messages with warm, full replies keeps the loop running and makes it harder for you to step back. Shift to shorter replies, let some messages go without a response, and let the thread cool. You do not need to announce that you are done. Simply stop initiating and respond at a more ordinary pace.

If he comes back with a real plan after a gap, you can decide then whether to engage. If he keeps circling without ever committing, you can choose to stop. Give it a reasonable window, perhaps a couple of weeks of him not making any real move, and then let it go. Staying in an ambiguous thread indefinitely costs you time and attention that could go to someone who is clearly interested.