The telephone teaches us a useful lesson. At its peak in 2008, there were 1.3bn landlines for a global population close to 7 billion. Today more than 6 billion people have a mobile phone – more than have access to a toilet, according to a UN study. Many assume that the mobile succeeded where the landline failed, because the superior technology made widespread coverage more possible. There is something to that. But the main reason, simply, is that, to get a landline, you need a bank account and credit. About half of the world’s population is “unbanked”, without access to the basic financial services you need. Telecoms companies saw no potential custom, the infrastructure was never built and many were left with fewer possibilities to communicate. But a mobile phone and its airtime you can buy with cash.

http://www.theguardian.com/money/commentisfree/2016/mar/21/fear-cashless-world-contactless