Before it became one of the biggest hits of the 1990's, Seinfeld was yet another unsold pilot, burned off by NBC in the middle of the summer. The show didn't set the world on fire, but critics praised it, surprised that NBC hadn't ordered a full season.
An NBC executive became bullish on the show and convinced the network to let him fund more episodes out of his department's own budget. Only four episodes were ordered, but it was enough. The show would get a second season based on the results- a wise decision.