The question also applies to organizations, like HL7 International, or IHE USA. And again, the idea that "grown up" is a done thing applies even less to organizations that it does to people. Growing up is a process of change. Organizations need to be constantly changing to meet the needs of their environment.
And people will either resist or promote change. It's not comfortable, but the alternative is even worse.
Remember this, when an organism (person or organization) stops changing, it isn't because they've reached perfection, but rather, because they have died.