To be able to send a message at a specific date and time in the future. For example when I know a birthday is coming up but I'll be asleep at midnight when it turns into their birthday, I scheduled a msg to be sent to them at midnight and I do t have to be awake to send it. Or when I work overnights and I need to text someone that works a normal schedule, I don't want to wake them with a text in the middle of the night but I don't want to end up forgetting by morning either. So I schedule the msg to be sent at a time I think they would be awake and then I can forget about it until they reply. And sooooooooooooooooo many more uses!!