Why does a nonlinear career path stall at senior level?

Because a senior hire gets defended, not just assessed. A nonlinear career path widens the range of work you can do and narrows the range a search process can easily justify you for. Recruiters read breadth as risk they have to argue away, so interest arrives early and confidence never follows.

Is a nonlinear career path a disadvantage for executive roles?

Not in capability terms. It changes what a hiring process can easily defend rather than what you can do, which makes it a legibility problem rather than a competence one. That distinction matters because the two call for different responses. A capability gap closes by building something. A legibility gap closes by translation, by evidence a stranger can read without you present, or by a route that does not require anyone to defend an unfamiliar record to a committee.

How do I explain a nonlinear career path to a recruiter?

Lead with the problem you solve for a particular kind of organization, stated narrowly enough that someone could disagree with it, rather than a title or a chronological summary. A recruiter needs a sentence they can repeat to a client, so give them one. Before investing heavily in wording, check whether explanation is genuinely what blocks you, because effort spent on a legibility problem you do not have produces nothing.

Can a career coach get me an executive role?

No. Tandem does not place candidates, run executive search, write CVs or supply access to employers, and any coach promising an outcome of that kind is describing a different service. Career transition coaching works on direction, on the evidence behind your claim, on how the market reads your record, and on the constraints your life imposes. The external moves remain yours, and so does the decision.