fast-food
(4)
Jack in the Box
Jack in the Box built a 75-year business by refusing to choose between burgers, tacos and breakfast. Now the San Diego chain has to prove that its appetite for variety can survive a leaner, more disciplined era.
Del Taco
The Mojave taco stand that grew into America's number-two Mexican drive-thru now serves fries next to burritos, runs a loyalty app with four heat-rated tiers, and just changed hands for the second time in three years.
The Wendy's Company
Wendy's turned a square hamburger, fresh beef and a sharp online voice into a global franchise system. Its next act is less nostalgic: make thousands of restaurants feel worth the trip again while the value wars squeeze every drive-thru.
McDonald's
The Golden Arches sell burgers, but the durable product is a system - franchise economics, high-traffic real estate, supply-chain discipline and a loyalty app now used by nearly 210 million active customers.