Pete Townshend is pretty much the only person on the planet who sees the Who's 1971 LP, Who's Next, as a failure. To him, it's the sad remains of his crazily ambitious rock opera Lifehouse that he ultimately aborted. He doesn't even like the cover art or the name of the album.
Explaining Lifehouse would take about 15,000 words and a couple of flow charts, so let's just say it's a complex science fiction rock opera that anticipated the coming of the Internet. "Behind Blue Eyes" is the theme song of the villain, Jumbo. When it hit the radio in 1971, almost nobody knew that, but it didn't matter: it shot up the charts all over the world and has been part of their live show for over 40 years.