A majority of the physical work is done by the horses, of course, and it looks like the drivers (Top level management) are slacking off - but everything is really on them. "Strategy" is really just where to go and which route to get there. And if they choose wrong or time things badly, everyone else in the organization has done their work correctly, and the failure is purely executive.
The workers are great at running (execution), but left to themselves are horrible at self organizing and running in the direction required in tandem, with the correct beat and stride. It doesn't matter how strong or fast the individual horses are, it's much more important that they run together without friction or distraction and support each other.
That's where (good) management comes in. They're the blinders that keep the horses from individually pulling in different directions and chasing distractions, and the harnesses that keep the entire team fixed together. The exert pressure on horses to both slow down and speed up, and both are vitally important. Done well, management is critical to making sure that the whole org works smoothly. They also act as a communication bridge between strategy and execution. Strategy is great for the all hands once a week or month, where the execs sing about the promised land, but the weekly plans, budgets, and responsibilities of making sure everyone is fed and has toilet access are all management.
Bad managers typically suffer from delusions of being either horses or drivers. They either try to work hard like the horses (bad idea - there's no harness or blinders), or think they're in charge of strategy (they're seen as just slackers, and no harness or blinders again). They don't temper executive vision with their knowledge of reality, nor do they transitively inspire workers.