The restriction is in place for two reasons: Firstly, we want to protect our female users from having overflowing inboxes and, secondly, we want to make sure that messages are more meaningful. It takes more than just a “Hi, how’s it going?” (in most cases at least) to stand out from the competition and get someone’s attention. At the same time, icebreakers can’t just be ignored, they need to be responded to.