Being a great director has little to do with being a great artistic director.
Directors direct projects. Artistic directors use a collection of projects to fulfill a mission that serves a community. These are completely separate skills.
ADs who direct some projects for their own company risk treating those projects as precious. Too often, they break rules for their project (organizational mission, budget, marketing, etc.) that they would never allow an “outside” director to break.
And in too many cases, when the identity of a nonprofit arts organization is too closely entangled with the vision of an artistic director, the organization’s brand is that much more difficult to recuperate when inevitable leadership change occurs.
After all, succession is not merely an artistic director handpicking a successor, is it? A company is greater than any individual leader, right?