You're describing life under caretaker CEOs, which true to form are a self-fulfilling prophecy for mediocrity. The vast majority of large public CEOs are caretaker CEOs, and it's why working for large public companies can feel so slow and dreary.
But then you get turnaround CEOs, the ones the board hires because the company is in dire financial straits, who comes in, fires executives, sets new strategy, communicates openly and plainly across all layers of management and labor. Things can change quickly under the right leadership.