The key message in this book is:

Start-ups should use a semi-scientific approach to test their core assumptions and then build a sustainable business model on the validated hypotheses.

They should develop product prototypes quickly and then continuously refine them by gathering customer feedback and going through build-measure-learn loops.

The questions this book answered:

Which main goal should a start-up pursue and how?

Start-ups need to be managed differently from established companies.

The purpose of a start-up is to find a sustainable business model.

Find your sustainable business model through validated learning.

How can start-ups find the right product and business model?

The leap-of-faith assumptions: test your value and growth hypotheses.

Develop a minimal viable product to test your idea in the market.

Build, measure, learn – as fast and as often as possible.

To find the right business model for you company, you usually have to pivot.

How can start-ups find their engine of growth and how can they analyze the right metrics?

Every start-up should initially focus on one engine of growth.

Vanity metrics are often flattering but misleading– they won’t help you find a sustainable business model.

Every start-up has to define its core metrics and analyze them properly.