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People lie about your idea

How to hear what people will really do, not what they say to be kind · 14 min

In 2005 a Nairobi pilot was built so borrowers could repay small loans by phone. On the screens, people were doing something else: sending money home. Eleven years later a $699 juicer raised $120 million before someone squeezed a pack by hand. Why a yes is inflated, the questions people can't lie to, and three conversations before Friday.

Takeaways

  • In a field experiment with two hundred and sixty-seven people in Kentucky, forty-five percent said they would buy a programme at a given price; when the same offer was real, twenty-six percent bought. Asking the first group "are you definitely sure?" brought their yes down to twenty-four percent, almost exactly the real number. Across twenty-eight studies that compared stated and real willingness to pay, people overstated by about a third in the middle case, and by far more at the top.
  • The questions people cannot lie to are about the past, not the future: when did this last happen, what did you do about it, what did it cost you. If they have never tried to solve it, they will not buy your solution. A compliment means you pitched; a real answer ends in time, money or a next step.
  • Something to try: before Friday, three conversations with people who have the problem, using only past-tense questions, and listening for one thing: money or time they have already spent on it.

Chapters

  1. A web page in Nairobi0:17
  2. Just ask them1:55
  3. Questions people can't lie to3:45
  4. A phone and a juicer5:44
  5. Same praise, different problem8:34
  6. Build yours10:08
  7. The answer11:56

References

  1. Hughes, N. & Lonie, S. (Innovations: Technology, Governance, Globalization) — M-PESA: Mobile Money for the "Unbanked": Turning Cellphones into 24-Hour Tellers in Kenya(2007)
  2. FSD Kenya (Financial Sector Deepening Kenya) — An overview of M-PESA(2015)
  3. Leaders League — Susie Lonie (M-PESA): "I knew it was going to be big" (Part I)(2015)
  4. Safaricom PLC — Safaricom PLC condensed audited results for the year ended 31 March 2025(2025)
  5. Huet, E. & Zaleski, O. (Bloomberg) — Silicon Valley's $400 Juicer May Be Feeling the Squeeze(2017)
  6. Huet, E. & Zaleski, O. (Bloomberg, via The Jakarta Post) — Silicon Valley's $400 juicer may be feeling the squeeze(2017)
  7. NPR (The Two-Way) — Juicero CEO Says Luxury Juicer Is 'Much More' Than Juice; Internet Is Unimpressed(2017)
  8. Kowitt, B. (Fortune) — The Maker of the Infamous $400 Juicer Is Shutting Down(2017)
  9. Klineman, J. (BevNET) — Juicero Says It's Shutting Down(2017)
  10. Aouf, R. S. (Dezeen) — Company behind Yves Behar's hard-pressed Juicero machine shuts down(2017)
  11. Blumenschein, K., Blomquist, G. C., Johannesson, M., Horn, N. & Freeman, P. (The Economic Journal) — Eliciting willingness to pay without bias: evidence from a field experiment(2008)
  12. Murphy, J. J., Allen, P. G., Stevens, T. H. & Weatherhead, D. (University of Massachusetts Amherst; published in Environmental and Resource Economics, 2005) — A Meta-Analysis of Hypothetical Bias in Stated Preference Valuation(2003)
  13. Murphy, J. J., Allen, P. G., Stevens, T. H. & Weatherhead, D. (AgEcon Search record) — A Meta-Analysis of Hypothetical Bias in Stated Preference Valuation(2003)
  14. Fitzpatrick, R. — The Mom Test: How to talk to customers & learn if your business is a good idea when everyone is lying to you(2013)
  15. Fitzpatrick, R. (text hosted by The Forge, McMaster University) — The Mom Test(2014)
  16. Lynch, M. (mtlynch.io) — The Mom Test by Rob Fitzpatrick
  17. Fitzpatrick, R. (robfitz.com) — Bias is never 0%, validation is never 100% // Context and pragmatism in custdev(2022)
  18. Fitzpatrick, R. (robfitz.com) — Customer convos are the carpenter's hammer // Pick the right tool for the job // Validation Quads v0.9(2022)