Every creative is prone to bouts of self-consciousness once in a while. No matter how many incredible things a human being can create, there's no guarantee that such a hot streak can last forever.

By the time he was in his forties, Rod Serling seemed to believe he'd hit a wall in his career.

"I don't mind saying that I haven't turned out a stellar writing performance in the last seven years," said Serling during a 1969 interview with the Miami Herald-Copley News Service.

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Previously, Serling had created The Twilight Zone, a series that enjoyed immense success. However, he felt that his more recent attempts at writing weren't up to par, like his original screenplay for the Planet of the Apes (1968).

"In the first place, I wrote the storyline but not the dialogue for Planet of the Apes," said Serling. "And they didn't use my ending."

Serling also found himself fielding countless offers to write and direct more commercial, conventional stories, like commercials. Serling acknowledged that these opportunities were not only lucrative, but they sometimes guaranteed greater success than his more creative endeavors.

"It's not easy to turn down," said Serling. "For one aspirin commercial, they pay me a fast $4,000 up front, and it'll bring in, oh, maybe, $15,000 a year - all this for 20 minutes' work in an afternoon. On the other hand, I can work months on a script and it may not satisfy me or a producer, and that's time down the tube."