Takeaways

• In July nineteen ninety-nine, a few weeks after opening, the online grocer Webvan agreed to build up to twenty-six more warehouses, at an estimated cost of about one billion dollars; by early two thousand and one its Oakland warehouse averaged about two thousand one hundred and sixty orders a day against a break-even of about three thousand and a capacity of eight thousand, and it shut down in July. In two thousand and seven and two thousand and eight, Dropbox showed short videos before its product was ready; one took its waiting list from five thousand to seventy-five thousand people in one day.
• A sign-up shows who is curious; a price shows who is serious. In a door-to-door field experiment with more than a thousand households in Lusaka, Zambia, those who agreed to a higher price for a water-cleaning liquid were more likely to actually use it, while the amount they finally paid made no consistent difference. One city, one product: a filter, not a law.
• Something to try: before Friday, a test that needs no building: a plain description that says it is not ready yet, a picture or short video, and a way to commit that costs something, such as a small deposit you will refund in full if you do not deliver.