I think the core problem is that it assumes you know what part of the software will need to be changed. But you often don't so you end up with code that is too

I think the core problem is that it assumes you know what part of the software will need to be changed. But you often don't so you end up with code that is too rigid in places that you need to be flexible and too flexible (i.e. complex) in places that don't need it.