New hire onboarding reveals your documentation quality.
If onboarding requires weeks of shadowing, constant questions, and tribal knowledge transfer, your documentation is failing.
Good documentation means new people can get productive fast. They read the docs. They understand the context. They start contributing.
Use each new hire as a test. Where do they get stuck? What did they have to ask about? Those are documentation gaps.
Have new people improve the docs as they learn. They see the gaps clearly because everything is unfamiliar.
Onboarding should shrink over time. Each hire makes it better for the next.