Reference #195: The First 90 Days
As you rise in an organisation, influence becomes more important than positional authority. This is for two major reasons.
At higher levels, the issues you face are more complex with fewer immediately obvious answers. Decisions are shaped by trusting others and mutual support.
There are also more capable people with stronger egos at these levels. And so decision-making becomes more intense and politically charged.
Watkins. The First 90 Days, 2013. (22-23)