The Lean Startup: The Million Copy Bestseller Driving Entrepreneurs to Success

by Eric Ries

Instead of making complex plans that are based on a lot of assumptions, you can make constant adjustments with a steering wheel called the Build-Measure-Learn feedback loop. Through this process of steering, we can learn when and if it’s time to make a sharp turn called a pivot or whether we should persevere along our current path.

What differentiates the success stories from the failures is that the successful entrepreneurs had the foresight, the ability, and the tools to discover which parts of their plans were working brilliantly and which were misguided, and adapt their strategies accordingly.

As we’ll see in a moment, this is a common danger. Companies of any size that have a working engine of growth can come to rely on the wrong kind of metrics to guide their actions. This is what tempts managers to resort to the usual bag of success theater tricks: last-minute ad buys, channel stuffing, and whiz-bang demos, in a desperate attempt to make the gross numbers look better. Energy invested in success theater is energy that could have been used to help build a sustainable business. I call the traditional numbers used to judge startups “vanity metrics,” and innovation accounting requires us to avoid the temptation to use them.

Imagine another pair of businesses. The first makes $1 on each customer it signs up; the second makes $100,000 from each customer it signs up. To predict which company will grow faster, you need to know only one additional thing: how much it costs to sign up a new customer.