Any company that does not reinvent itself (whether small or large) is going to die. It is not about the size, but rather about the intent and the choices they have made.
Smaller companies can make choices much more easily because their downside is limited, which can lead to a bias that small companies are going to kill the bigger ones. If big companies are aware, agile and aggressive - they can do magic.
So, it is more about taking decisions (which is about managing risk), moving fast, and challenging status quo.