Start-ups are, if anything, exercises in iteration. Hypotheses are formed, tested, adapted, retested, and a given company's center of gravity, culture, and path are forged in the fire of trial and error.
As an early stage venture investor, it is interesting to think about the minimum number of iterations required before a company is sufficiently baked that one's capital will be used to refine, rather than to reinvent, a given business.
Refinement and course correction are fundamental to start-ups, reinvention, however, is more related to inefficient capital consumption than it is to value creation.
I often state that genius is a function of context. The best ideas and the most valuable innovations germinate from real world observations of customer need.
Said another way, projections are dangerous, while rejections are instructive.
Start-ups, without any a priori knowledge of the customer need/problem, often project need and develop solutions in isolation and without the bearing of market reality - similar to Plato's Allegory of the Cave. It is always best to ensure that inputs are a function of reality (light of the sun) rather than projection (shadows on the wall).
My personal view is that the minimum number of iterations may be hard to quantify, however, I have observed that the best time to meet a company is ~T+6months. 6 months of commitment, iteration, and market reality seems to be the optimal balance between opportunity and trial and error.
The maturity of the plan, product spec, pitch, value prop, team's commitment, etc is exponential across time - the job of the early stage VC is to work out how much time and how many iterations and if a given company presents the optimal mix of both factors.