When you invest internally, you maintain strong institutional knowledge and culture. You deepen the commitment and the connection to the project. This is just a win-win-win for any company. I've seen it continuously result in boosted productivity, quality, and overall mood/energy in the office.

Contrast that with the usual approach of hiring anybody and everybody rapidly, and then pulling in outside execs that bring in their own VPs and decimate the existing culture. This signals to all the talented people in the company that they will not receive a promotion, but instead by replaced when necessary. They will just jump ship at that point and get a promotion elsewhere.