According to The Guardian, McCartney and his legendary writing partner and bandmate John Lennon simply forgot dozens of potential hits simply because of the lack of today's technology.

"We didn't have tape recorders. Now you can do it on your phone," McCartney said. "So you would have to form the thing, have it all finished, remember it all, go in pretty quickly and record it. Now, because you can get things down on a device, I've got millions of things I want to record and do."

But forgetting some songs might have helped the group, he said.

"You had to write songs that were memorable, because you had to remember them or they were lost" McCartney said.

From "I Wanna Hold Your Hand" to "Magical Mystery Tour," and "Revolution," The Beatles created songs that are still popular 40 years after they broke up.

"Revolution" was featured in the recent Universal "Minions" movie.

Julie Taymor directed "Across the Universe" in 2007, a movie musical with a complete soundtrack of Beatles songs.