Thomas Edison revolutionized modern life with such innovative inventions as the phonograph and the incandescent light bulb. But his prolific experimentation also meant that failure was a given. Edison saw those moments as stepping stones, saying, “Our greatest weakness lies in giving up.” Progress hardly ever happens in a straight line, and it almost always comes with its fair share of setbacks. Success is the product of many things, but perhaps most importantly, it comes down to persistence.