AFAIK that usage traces back to the 1990s TV show "Quantum Leap", in which the protagonist would travel in space & time to a new place each episode.
The phrase 'Quantum Leap', then, was popularly taken to mean a large change.
The damage done to the vernacular by that show's title is only exceeded by the damage done to the vernacular by another piece of 1990s popular culture, Alanis Morissette's song 'Ironic'.
The phrase 'Quantum Leap', then, was popularly taken to mean a large change.
The damage done to the vernacular by that show's title is only exceeded by the damage done to the vernacular by another piece of 1990s popular culture, Alanis Morissette's song 'Ironic'.