They'll send a personalised introduction text, wait for a response and, upon receiving it, send an acknowledgement. They will engage 10% of their country's population. And they will limit the voting to one hour. Let's do some back of the napkin math: that's 2 outbound + 1 inbound message for every participant. Let's say there are around 7 million of them. All this needs to go down in one hour, or 3600 seconds. That's average of ~4000 outbound and ~2000 inbound messages per second, which all need to be properly paired up and processed individually. They all need to go through the billing process, all need to be routed to the most reliable telecom operators and their delivery needs to be tracked and reported back to the client. And all this needs to happen without interfering with existing traffic from other clients.