Roman dodecahedrons have been found across Europe, yet no ancient text explains what they were used for. Over the years, theories have ranged from practical tools to ritual objects, but none fully fit ...

March 6, 2026 • What do we want from sports? The very best athletes competing as hard as they know how, putting all their effort and training and natural ability to the test against their opponents.

Twenty years after the introduction of the theory, we revisit what it does—and doesn’t—explain. by Clayton M. Christensen, Michael E. Raynor and Rory McDonald Please enjoy this HBR Classic. Clayton M.