Late in every executive hiring process somebody asks for a ninety day plan. It is a fair request and it produces a bad document, because a candidate writing it has met four people, seen no data, and talked to zero customers. What they can produce is a plausible sounding plan for a generic company, and the ones who are best at producing it are not reliably the ones who are best at the job.
I have written these and I have read them. The good ones and the bad ones look nearly identical on the page. Both have a listening tour in month one, quick wins in month two, and a strategy in month three. The difference between them only becomes visible when reality arrives and the plan meets a fact nobody mentioned during interviews, which happens in roughly week two, every time.
A plan written from outside the company is a writing sample, not a plan. Grade it as one.
If you are hiring, replace the request with something that has actual signal in it. Give the candidate three real artifacts, a pipeline report, a churn cohort, a homepage, and ask what they notice. Or describe a decision you got wrong last year and ask how they would have argued it at the time. Both of those surface judgment under incomplete information, which is the thing you are actually buying.
If you are the candidate, write it anyway, but write it honestly. Name the three questions you would need answered in week one and what you would do differently depending on each answer. It is a less impressive document and it is a far better predictor. The hiring managers who prefer the polished version are telling you something useful about how they will behave when your real plan hits a fact they did not like.