I've been fascinated by the relationship between the inner child theory of enneagram that suggests that the core type is a defense mechanism sprung up around some sort of rejection of the native's truest state of being, which is their integration point. And the "
missing piece" theory, which states that a direct movement to the integration point is impossible, and that we must instead master the lessons of the disintegration point in order to move forward.
Taken together, it seems to point to a couple of things. The first is the idea that we might reject the integration point, because we've rejected its traits in ourselves. The second is that growth in terms of the ennegram is not a point to point thing, but more a both, together kind of thing. It might be helpful to think of one's path to growth, then, as being a balance between the core type and the stress point with the integrated point as the fulcrum, rather than integrated<---core<----stress. The following third point is to understand the stress as the antithesis to the defenses of the core, rather than the wholeness of the integrated type.
I say all that to get to the idea that the process of growth in the enneagram is really about growing closer to your true self, than anything else. The core type is not the true self, the integration point is.