The Songwriting Process

Wikipedia describes how Metallica’s hit “Enter Sandman” emerged from a single guitar riff:

Metallica’s songwriting method involved lead guitarist Kirk Hammett and bassist Jason Newsted submitting tapes of song ideas and concepts to rhythm guitarist James Hetfield and drummer Lars Ulrich, who then used the material in conjunction with their own ideas to write songs in Ulrich’s house in Berkeley, California. “Enter Sandman” evolved from a guitar riff that Hammett wrote. Originally, the riff was just two bars in length, but Ulrich suggested that the first bar should be played three times. The song was quickly finished, but Hetfield did not come up with vocal melodies and lyrics for a long time. The song, in fact, was among the album’s last to have lyrics, and the lyrics featured in the song are not the original; Hetfield felt that “Enter Sandman” sounded “catchy and kind of commercial” and so to contradict the sound, he wrote lyrics about “destroy[ing] the perfect family; a huge horrible secret in a family” that included references to crib death.

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Lars Ulrich described “Enter Sandman” as a “one-riff song”, in which all of its sections derive from the main riff that Kirk Hammett wrote.

Source: Wikipedia