Asynchronous circuits are very hard to design and prove correct unless they are very small, though there are abstractions that work for specific cases. Debuggin

Asynchronous circuits are very hard to design and prove correct unless they are very small, though there are abstractions that work for specific cases. Debugging race conditions and metastability problems, or proving that they can't happen, is no fun. But there's massive support for synchronous logic design, it is a well-understood discipline.