Here’s a modern-day retelling of Aesop’s fable of the tortoise and the hare. A $6 billion movie-rental business at the peak of its power abruptly dismisses a two-year-old startup’s offer to merge. Like the hare, the movie-rental business keeps running—in its case, growing for another four years. But six years after that, the business declares bankruptcy, eclipsed by the startup, which launched streaming video. In his new book, co-authored with Erin Meyer, No Rules Rules: Netflix and the Culture of Reinvention, Netflix CEO Reed Hastings describes in a handful of words the decade it took his company to overcome Blockbuster: “little by little, the world changed and our business stayed on its feet and grew.”...