[silentbicycle]

A lot of intros to Erlang miss an important point: Erlang is about fault tolerance, not concurrency. The concurrency is a means to an end -- if your systems has to survive process crashes, hardware failures, and so on, it needs to have multiple components that can supervise and restart each other. Unlike (say) node.js, in Erlang, error handling is priority #1. Its ability to juggle lots of concurrent connections is just a consequence of its priority on localizing errors.

Also, Erlang tries to address many failure cases that other languages/platforms do not; this isn't free. It's often a good trade-off (making systems resilient after the fact can be quite an undertaking), but worth noting.