[Prokopton]

The critical factor was that VHS could put an entire movie on a single tape.

But to do so they had to slow the speed down, seriously degrading PQ.

[Locomotive Breath]

Absolutely. But most people can't tell the difference in PQ, but they can tell the difference when they have to get up in the middle of the movie to swap tapes. And that they have to store both tapes together to keep the movie in one place. And when they can't set their VCR to record the entire game and miss the final five minutes. And so forth.