Scala projects are difficult to maintain
I had a startup that went all in on scala.  By the time we realized we chose the wrong language it was too late.<p>Complexity is the primary issue with the scala language... when the whole goal is to have a scalable language which in itself is diametrically opposed to simplicity, your language is dead on arrival.<p>After using Scala, Go seemed like a dream come true.<p>We really loved the integration of OO and FP, really miss the FP awesomeness honestly... but simplicity trumps doing either of those things well.