Right. That's why we need to know email address.
It's sometimes inconvenient.

Of course, SMS isn't a leading role also here.
We use kinds of SNS to communicate with friends but it's not useful at work.

I often receive SMS late at night.
"I sent you a document you need."
And then, I work again using the document though I want to go to bed.
Hmm... Cellphone including SMS should die at work.

Happy birthday!
SMS is more popular today than a few years ago because we can send it between different network operators.
Actually, we didn't have the SMS, possible to send to any phone, until July 2011.

In Japan, I think they don't/won't panic. Patient is their default configuration.