“Then suddenly, in 1998, Erlang was banned within the Ericsson. The reason? To avoid the costs of development of a language that was unique to Ericsson, and instead to access the shared effort being put into the development of other languages.”
Ericsson built Erlang for telephone switches and banned it in 1998 to save money. The team got it released as open source that December. WhatsApp ran it from 10 million users in 2010 to 400 million and sold to Facebook for $16 billion in 2014. Ericsson paid for the research and two founders became billionaires on it.