Stuck in "always done this way" mentality.
I lot of what we do might have worked in the past, and still works today, but that doesn't mean that it's the best, or even proper, way of doing it.
Changes must be done to adapt to current needs, and often leading people in the organization don't pursue new ways to improve.
"If it's not broken, don't fix it!" is not the same as "how to make this better next time?"