I've seen some blog posts about software developers just being hired learning a new language so that they can build their companies' next program. Personally, I've always believed that developers should already know the language since they're new to the company (and know what language the program will need). To expand on that, it's not like an old employee who was hired for say, their Java skills, who now need to build a C# program.
So my questions is, why do some companies hire developers with no language experience instead of those with the specific language experience? Presume that all non-programming related factors are equal.
Related, what commentary can you share about learning a language on the job (if you have done so)?