With a normal call, you follow typical social conventions of: ring ring ring ring pickup "Hello" "Hey Morsch, what time are you doing $foo task by today?"

With a normal call, you follow typical social conventions of: ring ring ring ring pickup "Hello" "Hey Morsch, what time are you doing $foo task by today?" "Probably 6:30pm." "Okay thanks." "Do you need anything else?" "No, that's it, I'll talk to you later." "Alright bye." "bye" hangup With PTT, there is a social convention surrounding it too that allows you to be much more abbreviated without coming across as rude: chirp (being talking immediately and assume that morsch hears you "MOrsch you out there?" "Yeah what's up?" "What time are you doing $foo" "6:30" "Thanks." end. PTT occupied a space between a phone call and an SMS/email. It was like SMS, but urgent, and you didn't need to pick up your phone and type a response. It's the same reason logistics, stage production, building, etc. all use walkie-talkies instead of phones or SMS. PTT was that sort of goodness, but it was global.