Why net present value rule matters to a first-time founder
The rule turns future cash flows into today’s value and tests whether a project is expected to earn more than the required return. It can help founders compare investments with different timing. Its answer is only as reliable as the forecast, discount rate and risks built into the model.
Examples of net present value rule
A machine costs £100,000 today. Discounted expected cash inflows total £118,000, giving an NPV of £18,000, so the rule supports accepting it. If demand is uncertain, the founder should also test lower sales, delays and higher costs rather than rely only on the positive base-case figure.
Common misunderstanding
A positive NPV is not a guarantee of profit or cash availability. It is an estimate based on future cash flows and a discount rate representing time and risk. The rule also does not resolve capital rationing automatically when several positive-NPV projects compete for limited money or staff.
When to use it
Use it for material projects, acquisitions or product investments where you can estimate incremental cash flows and choose a defensible discount rate. Compare scenarios and record assumptions. For a cheap, reversible experiment, detailed NPV modelling may add false precision and cost more time than the decision warrants.