FP Complete is a consulting company. They promote Haskell, and they boast about getting hired to help a company analyze their code base to fix a space leak. I wouldn't trust my business to a language that requires hiring a consulting firm to do fundamental debugging. I've written memory leaks, but never needed to hire consultants to debug them.
Consulting is rarely about helping problems that too hard to fix by a good developer. They're often about helping problems that the customer doesn't want to put (or hire) good developers on.
Haskell is lazy by default, and sometimes builds up large unevaluated expression trees that need to be forced. Other languages are eager, but litter the code with abstractions like Callables and Futures and channels just to not do something.
