By Marty Cagan · svpg.com · LinkedIn
Marty Cagan argues that a product proving it works and is usable is not the same as a product people will actually choose to buy and use. He calls the smallest functional, usable version a 'Minimal Product' and reserves 'Viable Product' for one that customers select and that can sustain a business. Teams often mistake a successful usability test for product-market fit, then blame sales or marketing when adoption stalls. Cagan says the 'would you use it?' question is harder and riskier than 'could you use it?', so discovery effort should concentrate there.
01Key takeaways
- Usability testing alone does not validate product-market fit; it only shows the product can be used.
- Ask whether customers would choose and keep using the product, not merely whether they could use it.
- Reasons people reject products include price, satisfaction with current solutions, and high switching costs.
- Distinguish a minimal working product from a viable one that customers pick and that supports a business.
- Spend most discovery effort on viability, the riskiest part of the equation.
02Key sections
- The usability trap
- Teams often claim product-market fit based on usability tests showing users can complete tasks. Cagan points out that this only shows the product works, not that anyone will choose it.
- Could vs. would
- Cagan frames the critical question as whether customers would use the product, not whether they could. Many products function well yet fail because people have no reason or ability to switch.
- Minimal vs. viable
- A Minimal Product is the smallest version that works and is usable, while a Viable Product is one people choose to buy and use and that sustains a business. The gap between them is often large.
- Where to focus discovery
- The viability question is usually the hardest and highest-risk part, so teams should direct most of their discovery time there rather than at feasibility or usability.
03From the post
“A partnership dedicated to teaching best practices to product teams and product leaders”
04Frameworks mentioned
Summary and takeaways written by PM Atlas; quotes are short excerpts. © the original author.