This is a must-read. The Innovator's Dilemma explains why large established companies so often fail to compete against new entrants, and what you can to do to avoid this trap.

From Amazon:
​The bestselling classic on disruptive innovation, by renowned author Clayton M. Christensen.

His work is cited by the world’s best-known thought leaders, from Steve Jobs to Malcolm Gladwell. In this classic bestseller—one of the most influential business books of all time—innovation expert Clayton Christensen shows how even the most outstanding companies can do everything right—yet still lose market leadership.

Christensen explains why most companies miss out on new waves of innovation. No matter the industry, he says, a successful company with established products will get pushed aside unless managers know how and when to abandon traditional business practices.

Offering both successes and failures from leading companies as a guide, The Innovator’s Dilemma gives you a set of rules for capitalizing on the phenomenon of disruptive innovation.

Sharp, cogent, and provocative—and consistently noted as one of the most valuable business ideas of all time--The Innovator’s Dilemma is the book no manager, leader, or entrepreneur should be without.

This book was instrumental for me learning how to test ideas using data, fail fast, and keep a beginner's mindset as I approach new markets and products. Hopefully you get as much out of it as I did.

From Amazon:
Most startups fail. But many of those failures are preventable.  The Lean Startup is a new approach being adopted across the globe, changing the way companies are built and new products are launched. 

Eric Ries defines a startup as an organization dedicated to creating something new under conditions of extreme uncertainty. This is just as true for one person in a garage or a group of seasoned professionals in a Fortune 500 boardroom. What they have in common is a mission to penetrate that fog of uncertainty to discover a successful path to a sustainable business. 

The Lean Startup approach fosters companies that are both more capital efficient and that leverage human creativity more effectively.  Inspired by lessons from lean manufacturing, it relies on “validated learning,” rapid scientific experimentation, as well as a number of counter-intuitive practices that shorten product development cycles, measure actual progress without resorting to vanity metrics, and learn what customers really want. It enables a company to shift directions with agility, altering plans inch by inch, minute by minute. 

Rather than wasting time creating elaborate business plans, The Lean Startup offers entrepreneurs - in companies of all sizes - a way to test their vision continuously, to adapt and adjust before it’s too late. Ries provides a scientific approach to creating and managing successful startups in a age when companies need to innovate more than ever.