Conversation so far:
What type of music did the Beatles have with the album Sgt. Pepper's Lonely Hearts Club Band?
An important work of British psychedelia, the album incorporates a range of stylistic influences, including vaudeville, circus, music hall, avant-garde, and Western and Indian classical music.
How many albums did The Beatles have?
In their native United Kingdom, between 1962 and 1970, the Beatles released 12 studio albums (13 worldwide), 13 extended plays (EPs) and 22 singles.
Were there any hit singles in Sgt. Pepper's Lonely Hearts Club Band?

Question: What was important about the lyrics?
Self-contained rewrite: What was important about the lyrics from Sgt. Pepper's Lonely Hearts Club Band?