How long before a new scientific theory emerges to address a paradigm crisis

In each case a novel theory emerged only after a pronounced failure in the normal problem-solving activity.

Furthermore, except for the case of Copernicus in which factors external to science played a particularly large role, that breakdown and the proliferation of theories that is its sign occurred no more than a decade or two before the new theory’s enunciation.

The novel theory seems a direct response to crisis.