Tom Petty believed that a quote by Janis Joplin helped inspire one of his most enduring songs, 1981's classic "The Waiting."

"I love being onstage," Joplin once said, "and everything else is just waiting."

Petty said "that's where I think I got it from," in Paul Zollo's Conversations With Tom Petty. "[Roger] McGuinn swears that he said it to me. Maybe he did. I don't think so. I think I got it from the Janis Joplin quote. That's where it stuck in my mind. I don't think she said, 'The waiting is the hardest part,' but it was something to that effect: 'Everything else is just waiting.' And so that's where that came from."

After Petty "hooked it" with the song's chorus, he knew he had to "get the whole fish in the boat." He preferred composing in a linear fashion, so he then started writing the verses.

Watch the Video for Tom Petty and the Heartbreakers' 'The Waiting'

Petty said it was a "long, drawn-out process ... to write the song. I had a really good chorus, and I had to work backwards from the chorus. So that's always hard. But I was really determined that I was going to get it. And I got it. It just took me a long time. It took weeks of working on it."

His determination to build a song as good as its chorus came at the expense of everything else Petty was working on at the time. "If you're not lucky enough to get it all in one burst, but you know you've got something there, and there's any number of ways of getting it, any number of ways of completing it," he said. "But only one's gonna be right."

Petty's focus paid off. Released as the lead single from Hard Promises on April 20, 1981, "The Waiting" gave Petty and the Heartbreakers their third Top 20 Hot 100 hit – and a No. 1 on the Mainstream Rock chart.

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