I think this post also does a good job of explaining why explicit state machines see relatively little use in most systems. They require the user to decide which components should be in control. This is one of the things that can be really difficult to decide and double difficult for a group to decide. IME it is really only possible to convince someone with code in hand and therefore very groups will agree on the boundaries of the IoC early enough for them to pay off.
I think this post also does a good job of explaining why explicit state machines see relatively little use in most systems. They require the user to decide which components should be in control. This is one of the things that can be really difficult to decide and double difficult for a group to decide. IME it is really only possible to convince someone with code in hand and therefore very groups will agree on the boundaries of the IoC early enough for them to pay off.