The thing is, these types aren't usually complex in the way that logic is. Complex logic generally means lots of loops and conditions and such, maybe shared mutable state. Linear code that just calls a series of independent functions one after another is not generally considered complex, even though it may ultimately result in the execution of lots of code. What generally leads to these confusing errors is just simple types composed end-to-end. The problem is that while compilers are good at picking out the specific part of a function that's causing problems, they generally can't do the same thing with types, so it's kind of like if every time you got an exception, the entire module source was pinpointed as the problem.