Not really true, it gets easier the more languages you learn. I do know of developers who spent their whole working lives using only one language and they are very good at that one language. (I am thinking of MUMPS and the developers I met when working in the medical s/w field) Should we just learn one language and do we gain by knowing many and why are there so many languages that do the same thing? If there were to be one language what would it look like? https://en.wikipedia.org/wiki/MUMPS