I don't see the post claiming Erlang is the most efficient language out there. So I'm guessing you're just being a jerk here. But there are several definitions

I don't see the post claiming Erlang is the most efficient language out there. So I'm guessing you're just being a jerk here. But there are several definitions of efficiency in programming. Sure, it won't perform as well as a good optimizing C compiler. But Erlang does have pretty good performance, and it has great support for distributed processing. Using Erlang/OTP means you don't have to hack your way through distributed stuff, probably getting it wrong. It also has good support for upgrading code on the fly without taking down the system. In those ways, Erlang could be said to be more efficient than C.