It's a phenomenon that I'm sure occurs at many large companies as well as small companies.
The desire to hire people who have the ability to get things done, effectively navigate the organization.
How is it possible to find someone for a open position that already knows how to navigate the organization? They have to come from within the organization.
This requirement could lead to talent scalability issues for a growing company.
It could starve the organization of new ideas at higher levels. You're essentially only promoting from within. Entry level positions are the only way in.
This could be a sign that your internal processes need to overhauled to make it possible for anyone to come on board and contribute quickly.
There is a balance to strike between making it overly easy to navigate at the expense of speed.