validated learning is backed up by empirical data collected from real customers.

Cohorts and Split-tests Grockit changed the metrics they used to evaluate success in two ways. Instead of looking at gross metrics, Grockit switched to cohort-based metrics, and instead of looking for cause-and-effect relationships after the fact, Grockit would launch each new feature as a true split-test experiment.

a concept from Geoffrey Moore, who observed that companies generally follow one of two major business architectures: high margin, low volume (complex systems model) or low margin, high volume (volume operations model).6 The former commonly is associated with business to business (B2B) or enterprise sales cycles, and the latter with consumer

The extrapolation would not be perfect, but it would establish a baseline behavior that would be far more accurate than market research.

Following the lean manufacturing principle of kanban, or capacity constraint, Grockit changed the product prioritization process.

the customer is the most important part of the production process. This means that we must focus our energies exclusively on producing outcomes that the customer perceives as valuable.

FROM THE MVP TO INNOVATION ACCOUNTING The solution to this dilemma is a commitment to iteration. You have to commit to a locked-in agreement—ahead of time—that no matter what comes of testing the MVP, you will not give up hope. Successful entrepreneurs do not give up at the first sign of trouble, nor do they persevere the plane right into the

Learning milestones are useful for entrepreneurs as a way of assessing their progress accurately and objectively;

Cook explained that even though the product was missing features, the project was not a failure. The initial product—flaws and all—confirmed that users did have the desire to create event albums, which was extremely valuable information. Where customers complained about missing features, this suggested that the team was on the right track. The team