I find that some people prefer one kind of communication method over another. I keep my phone on silent and sometimes forget to check it for a couple of days, so text isn't a great way to get my immediate attention.

If I message someone and they don't get back to me, I remember how I am with texts and I assume that I chose the wrong messaging system. If I sent them an email, I will wonder if they got it or if it went into the spam folder. If I keep reaching out and they always take a while to get back to me, I usually just stop reaching out so much and also stop expecting a response from that person using that form of communication.