Say not in grief he is no more -- but live in thankfulness that he was.

If you're reading my blog, odds are you know who Clayton Christensen was. He passed away this week, and it was a loss to us all.

Everyone who writes about innovation stood on his shoulders.

His insights transformed the language and the practice of innovation.

Christensen changed the trajectory of my career and was the guide star for my work on innovation. I never got to say thank you.

Eye-opening

I remember the first time I read The Innovator's Dilemma, in 1997. Christensen, writing for a corporate audience, explained that there were two classes of products -- sustaining and disruptive. His message was that existing companies are great at sustaining technologies and products but were ignoring the threat of disruption.

He explained that companies have a penchant for continually improving sustaining products by adding more features to solve existing customer problems, and while this maximized profit, it was a trap. Often, the sustaining product features exceed the needs of some segments and ignore the needs of others. The focus on sustaining products leaves an opening for new startups with "good enough" products (and willing to initially take lower profits) to enter underserved or unserved markets. These new entrants were the disrupters.

By targeting these overlooked segments, the new entrants could attract a broader base of customers, iterate rapidly, and adopt new improvements faster (because they have less invested infrastructure at risk). They eventually crossed a threshold where they were not only cheaper but also better or faster than the incumbents. And then they'd move upmarket into the incumbents' markets. At that tipping point, the legacy industry collapses. (See Kodak, Blockbuster, Nokia, etc.)

Christensen explained that it wasn't that existing companies didn't see the new technologies or products or markets. They operated this way because their existing business models didn't allow them to initially profit from those opportunities -- so they ignored them, and continued to chase higher profitability in more-demanding segments.

Reading The Innovator's Dilemma was a revelation. In essence, Christensen was explaining how disrupters with few resources could eat the lunch of incumbents. When I finished, I must have had 25 pages of notes. I had never read something so clear and, more important, so immediately applicable to what we were about to undertake.

We had just started an enterprise software company, Epiphany, and we were one of those disrupters. I remember looking at my notes and realizing I held a step-by-step playbook to run rings around incumbents. All I had to do was exploit all the gaps and weaknesses that were inherent in incumbent companies.

We did.

Thank you, Clay, for opening my eyes.

Christensen's impact didn't end there. For the past 20 years, he inspired me to think differently about innovation and teaching.

Building better startups

After retiring, I began to think about the nature of startup innovation and entrepreneurship. It dawned on me that the implicit assumption startups had operated under was that startups were simply smaller versions of large companies. Over time, I realized that was wrong -- large companies executed known business models, while startups searched for them.

I went back and reread The Innovator's Dilemma and then a ton of the literature on corporate innovation. My goal was to figure out how to crack the code for startups like Christensen did for corporations. My first book, The Four Steps to the Epiphany, was a pale shadow of his work, but it did the job. Customer development became one of the three parts of the "lean startup" as Eric Ries and Alexander Osterwalder provided the other two components (agile engineering and the business model canvas). Today, the pile of books on startup innovation and entrepreneurship likely equals the literature on corporate innovation.

Teaching a different kind of innovator

Unlike corporate executives, founders are closer to artists than executives -- they see things others don't, and they spend their careers passionately trying to bring that vision to life. That passion powers them through the inevitable ups and downs of success and failures. Therefore, for founders, entrepreneurship isn't a job but a calling.

Understanding the students Clay was teaching gave me the confidence that we needed to do something different. The result was the Lean LaunchPad, I-Corps, and Hacking 4 Defense -- classes for a different type of student that emulated the startup experience.

Dropping the curtain on innovation theater

The next phase of my career was trying to understand why the tools we built for startups ended up failing (i.e., innovation theater) in companies and government organizations rather than creating actual innovation.

Here again I referred to Christensen's work, not only in The Innovator's Dilemma but also in The Innovator's Solution. He had introduced the idea that customers don't buy a product; instead they hire it for a "job to be done." And he offered a set of heuristics for launching disruptive businesses.

I realized what he and other management thinkers had long figured out. That if you don't engage the other parts of the organization in allowing innovation to occur, existing processes and procedures will strangle innovation in its crib. In the end, companies and government agencies need an innovation doctrine -- a shared body of beliefs of how innovation is practiced -- and an innovation pipeline, an end-to-end process for delivery and deployment of innovation.

Thank you, Clay, for all the inspiration to see further as an educator.

How to measure your life

For me, Clay's most important lesson, one that put his life's work in context, is his book How Will You Measure Your Life?

In it, Christensen reminds all of us to put the purpose of our lives front and center as we decide how to spend our time, talents, and energy. And in the end, the measure of a life is not time. It's the impact you make serving God, your family, your community, and your country. Your report card is whether the world is a better place.

He touched all of us and made us better.

Thank you, Clay, for reminding us what is important.

You left us way too early.