"What's the risk in trying out a new language? In reality, there really is none, you've just got to fight past it."<p>Counter argument (more  something that popped into my hard than something I firmly believe, but plausible):  As you get older you get a different perspective on time.   You increasingly ask yourself, Is this the best use of my time?  Are there not other things more deserving of my attention?<p>I do think that people tend to get a fear of failure instilled in them, and that contributes to lower motivation to try things, but adults also have different responsibilities than five-year-olds.