It's another barrier to entry. Documentation is probably the worst place to encounter a new language, since the reader is already confused and frustrated.

CoffeeScript is a nice language, but I think it's reputation suffers from it's association with Ruby. Far too many CoffeeScript tutorials are aimed at Rails devs who don't want to learn new syntax.

It's a lot of syntactic sugar and things removed. Even the ?: operator which I use a lot. Typing "a = if b then c else d" is a huge wasted opportunity to just keep the ?: op. Plus there's no way to get the == operator even if you know you want it and understand the nuances.

I honestly find I use the ? operator in coffeescript far, far more often than I want to use a ternary conditional.

Fair enough on the == operator, but it's another that I have honestly never needed or wanted.

If c is truthy: a = b && c || d