Why the Middle Management is the Key Success Factor for the Execution of Strategies

Middle Management is asked to carry out the strategy, but are they involved in the creation process? Do they understand the purpose if they get a report or presentation?

It is like often the problem of communication, consensus, and alignment. Only involved people will be able to go together in one direction. I believe companies could be more successful if they would work more on communication, engagement, culture, and feedback.