What makes men persist when they've already been told no?
For context, I (33F) went on three dates with a guy (36M) back in February. They were spaced pretty close together over the course of a couple of weeks. We got along nicely, he's an attractive guy and all but on the third date we went for a coffee and he fully tried to make out with me in the cafe and this put me off a bit. Later that day he asked me out again. I told him things were moving at a bit too quick of a pace for me and that I'd like to slow things down for now as I'm not yet feeling a romantic connection.
Then I started getting war and peace type messages asking me what I mean by slow things down, apologising for kissing me in the cafe, overdoing compliments, asking if I fancied him etc. It all came across as very insecure and a bit desperate and it put me off further, so I told him I'd enjoyed the dates but it was a bit too emotionally intense too quickly for me and we seemed to be in different places about that so probably best to not continue.
He's since initiated conversation 8 or 9 times on social media, ending each time with him asking me out again and me politely declining. In the second reach out he even said to me he has too much self respect to be someone's second choice and to keep reaching out after being rejected, but it's continued since lol.
I feel I've been very polite and honest in my responses but I find I'm just repeating myself every time he asks. I'm just curious as to what makes a guy do this as my friends have encountered similar when dating!