3. They’re angry at you
They won’t respond because if they do, they’ll say things they would regret. They will rather leave you on read.
4. They didn’t think an answer was necessary
There are some closing statements that just end the conversation. If I send you a message and you respond with “lol”, I will not say anything again. Why? Because there’s nothing to say. Unless of course, we start talking about a whole different thing altogether.