> The most common "why didn't you select me?" follow up answer I got was "we need someone who is an expert in XYZ language." Sometimes it was even that they nee

> The most common "why didn't you select me?" follow up answer I got was "we need someone who is an expert in XYZ language." Sometimes it was even that they need someone who is an expert in ABC library (when I was already pretty-much an expert in the language.) There's nothing really wrong with that as long as they advertise such and make it clear before even starting the interview process that you won't be hired unless you're a library ABC or language XYZ expert. The problem comes when they don't advertise that, bring you in anyway, and waste everybody's time.