The adaptation gap is the lag between what a new technology makes possible and how fast people and organizations actually reorganize to use it.
Electrification is the cleanest example. The dynamo went on sale in 1882, and the factory productivity payoff did not land until the 1920s, because the gains came from redesigning the factory around small individual motors, not from bolting one big one onto the old steam shaft. The machine was ready in a decade. The humans took four. That distance is where the whole story lives, and it is the easy half, the machine, that everyone watches while the hard half, the reorganizing, quietly decides who wins.
Its sibling is the augmentation gap: that one is the choice (replace people, or make them more capable), this one is the clock (how long the human side takes to catch up). Close the adaptation gap on purpose and you have started doing Human Acceleration.