The fact of human resistance is rarely accurately discussed or addressed by marketers, policy makers, and even educators. But the fact of the matter is that it takes twenty years for a genuine innovation of any kind–from an idea to a physical object–to change people’s actual lived behavior.

Whether that change is in a positive direction or a negative one.

If you’re building, whether in public or in private, not only should you bet on ten years to get to mastery in any discipline, but you should also bet on people accepting, using, and acknowledging what you’re building taking twenty years.

Human resistance is a deep abyss. Never bet against depth.