The most experienced hires receive the least onboarding, on the assumption that experience substitutes for context.
Why it matters when the plan changes
A senior hire's first months determine what they can achieve for years, because the relationships and informal routes they establish set what is available to them afterwards. Reading an organisation requires seeing five layers together, from formal design down to real ownership, dependencies and operating patterns; a new senior leader arrives with none of that reading done, and the more senior the appointment the less anyone feels able to explain the basics.
The tension is that what a new senior leader most needs is exactly what a formal programme leaves out: who actually decides, which dependencies are fragile, which past initiative still makes people cautious. Research on strategy execution found that only 9% of managers can rely on colleagues in other functions and units all the time, which is the layer a new leader has no way to assess and the informal network supplies only to people it already knows.
In practice
A division lead joins from outside with a strong record. Nine months later two initiatives have stalled on dependencies that everyone internal knew were fragile and nobody mentioned. The onboarding covered systems, policies and introductions, and covered none of what the job actually ran through.
Evidence
Onboarding covers the adjustment of new employees including role clarity and knowledge of organisational culture.
Onboarding, Wikipedia (2026)Cross-unit commitments are the least reliable part of execution, and they are the part a new leader has no way to assess.
Donald Sull, Rebecca Homkes and Charles Sull, Why Strategy Execution Unravels and What to Do About It, Harvard Business Review (2015)
What it cannot tell you
Senior-hire onboarding risk names a period of exposure; it does not specify when that period ends or measure whether a given hire has moved through it. It is silent on which dependencies matter most in a given organisation, and it does not distinguish a slow start from a genuine mismatch.
Questions
Because seniority is assumed to substitute for context, and because nobody feels able to explain basics to an experienced appointment. Formal onboarding, per the Wikipedia entry on Onboarding (2026), is meant to cover role clarity, yet the knowledge that determines effectiveness is held informally by people who assume it is obvious.
A map of who decides what, which dependencies the role runs through and which are fragile, what has been tried before and how it went, and who the real connectors are. None of that is in any document and all of it is available to insiders.
Until the person has built the relationships and context that let them work through the organisation rather than around it, which for a senior cross-functional role is usually two to three quarters. The formal programme typically ends in week four.
Not usually a failed appointment, but a slow one: initiatives stall on cross-unit dependencies, exactly the area Harvard Business Review's 2015 research found weakest, where only 9% of managers said they could rely on colleagues in other functions all the time. The damage is diffuse and rarely prompts a change in practice.
Giving the person an honest organisational read early, including what is unowned and what is fragile, and naming who the actual connectors are. That is a week of someone's time and it removes most of the discovery the first two quarters would otherwise consume.