Back in 2006, McDonald’s saw its growth stall. The fast-food chain decided that the problem was its limited menu, so it tried out a great many new items and ended up doubling the offerings. But sales hardly budged. Finally, in 2016, it took a new tack. It went back to basics, dropped most of those additional items, and instead extended its popular breakfast offerings. Sales finally jumped, with same-store revenue up 6% in 2017, and the stock rose by 40%.