Best, Base, Worst: Scenario Planning for Founders
Scenario planning for founders means comparing a small number of plausible operating cases rather than pretending one forecast is certain. The goal is not prediction. It is preparedness: change a few critical assumptions, then see how runway and decisions move across a best, base, and worst case.
On this page
- Build a base case for planning, a downside case for caution, and an upside case for ambition.
- Change only a few critical drivers first: customer growth, pricing, churn, and major costs.
- Scenarios show the range of likely outcomes and what actions matter most under uncertainty.
- Use scenarios to make decisions, not just to decorate a model.
What this means
A single forecast hides uncertainty, and founders then make hiring or fundraising decisions as if the future were settled. A good starting set is a best case, a base case, and a worst case. Change only a few critical assumptions at first: customer growth, pricing, churn, and major costs.
Why it matters
Scenarios help founders understand the range of likely outcomes and decide what actions matter most under uncertainty. The point is preparedness, not a false sense of precision.
A simple scenario set
Suppose monthly new customers are 40, 30, or 20 across the three cases, with price constant at 60 dollars. New monthly MRR added is 2,400 dollars in the best case, 1,800 dollars in the base case, and 1,200 dollars in the worst case. Even before churn, the operating story changes substantially.
Spreadsheet limitations
| Feature | Startup Suiteside by side | A spreadsheetthe manual way |
|---|---|---|
| Comparing cases | Compares scenarios side by side | Scenario tabs are possible |
| Switching assumptions | Controlled assumption switching | Manual setup gets messy quickly |
- Comparing cases
- Compares scenarios side by side
- Switching assumptions
- Controlled assumption switching
- Comparing cases
- Scenario tabs are possible
- Switching assumptions
- Manual setup gets messy quickly
Consultant limitations
| Feature | Startup Suiterecurring | A consultantperiodic |
|---|---|---|
| Best for | Internal, recurring scenario use | Stress-testing assumptions |
| Cadence | Ongoing operational planning | Often periodic |
- Best for
- Internal, recurring scenario use
- Cadence
- Ongoing operational planning
- Best for
- Stress-testing assumptions
- Cadence
- Often periodic
How Startup Suite helps
Startup Suite's Scenario Workbench is the comparison layer founders use before making expensive decisions. Set up best, base, and worst once, then read the impact on runway and funding timing at a glance.
Scenario Workbench: decide with the range in view
- Compare best, base, and worst on the same screen.
- Switch one driver and watch every case update together.
- See how each case changes runway before you commit to a hire or a raise.
A practical founder example
Say the base-case monthly operating loss is 12,000 dollars and the worst-case loss is 18,000 dollars. With 180,000 dollars of cash, runway moves from 180,000 divided by 12,000, or 15 months, to 180,000 divided by 18,000, or 10 months.
That five-month difference may completely change fundraising timing. Seeing it in advance is the whole reason to run scenarios rather than a single forecast.
Watch the 60-second summary
Best, base, worst
Frequently asked questions
How many scenarios do I need?
Start with three: best, base, and worst.
Should all assumptions change at once?
No. Focus on the most sensitive drivers first, such as growth, pricing, churn, and major costs.
Is the best case for investors?
Not by itself. Investors also want to see clear downside thinking.
Still have questions? Talk to the team.
