---
title: "Stage 5 — Decision math and reversibility (day 7–14)"
slug: "do-it-yourself-game-plans/stage-5-decision-math-and-reversibility-day-7-14"
section: "Do-it-yourself game plans"
description: "For each option show: cash spent before first evidence; time to first evidence; cash remaining if wrong; reversibility; people impact; legal dependency; an"
internal_only: false
---

# Stage 5 — Decision math and reversibility (day 7–14)

For each option show: cash spent before first evidence; time to first evidence; cash remaining if wrong; reversibility; people impact; legal dependency; and *what would make this option clearly inferior*. Keep probabilities as transparent subjective judgements when no data exist—never imply precision. For a SAFE or priced financing, run instrument-specific modelling and seek securities counsel; YC's SAFE materials describe why headline valuation alone is insufficient. [The SAFE — Y Combinator](https://www.ycombinator.com/safe)

**Deliverables:** one-page options grid with upside/downside and conditions. **Pitfall:** presenting a scenario spreadsheet as a forecast of guaranteed returns.