The other reason Betamax lost:
Recording time.
The original Betamax could only record 1 hour on tape, same as U-matic. JVC's VHS could do 2 hours, and they eventually squeezed 4 hours at LP (1/2) speed and 6 hours at EP/SLP (1/3) speed on a standard T-120 2-hour cassette. They wanted at least 4 hours because that was the average televised length of a U.S. football game.
Sony knew that slowing the tape speed would degrade the picture quality, and foolishly refused to do it. The consumer didn't mind, however. The buying public was willing to trade off higher picture quality for more recording time on tape. For the consumer, buying a single VHS tape was cheaper than buying multiple Betamax tapes.
Sony eventually did compromise, and got 5 hours on Beta-III, but VHS had already upped the ante to 9 hours on a T-180. By that time, Sony had already lost the war.
