I have this guy who Im interested in and when we speak, we laugh and its all nice, but he doesn't text me first anymore... I started texting him first and then the responses took longer. Usually we would answer within a day or later that day or early the next day... After his last response took 2 days, I didn't text first anymore and he hasn't texted me since. Fuck him. I liked him and was interested in proceeding things further but after that... Im not chasing. He could just say 'Im not interested" and not waste my time.
If a girl doesn't text you back within 24 hours, she isn't interested. Unless it's a one time event and she has something going on that day, but if it happens more than once, she's just not that into you. I guess it's the same for menn.