So why do people do that, like what a waste of time for both you and me, it's silly.
Most Helpful Guy
Less than 24 hours is way too soon to be declaring a guy to be ghosting.
Chances are, if this is being done through online dating, he is talking to multiple people at once. He may be trying to juggle a few different things, maybe another person is also wanting to see him Saturday. Or there is a game he wants to watch, or a show, or he has some other plans. He is waiting to hear back from somebody about what time they are free on Saturday so he can figure out what time he is free to see you... or something like that. At this stage I would be assuming his delay in response is because he is trying to maximize scheduling opportunities.
Have you sent him a follow-up asking him what time? Just tell him you sent him what times work for you, but you need to know what time works for him as you have other things you may do.
If you never hear back from him... yeah, he ghosted. Though it's not really a 'full' ghost if you've never even met. It's just rude, at that point. As to why he would do it... change of heart, most likely. Or something else came up that he preferred. But... as I say... too early to be assuming that.