The past few years have been a time of growth and challenges for quick-service restaurants (QSRs). These chains, generally thought of as "fast food" by consumers, have flourished: In total, they had more 350,000 locations in 2019, up from 300,000 in 2010. But that also means more intense competition as those fast-food restaurants  battle each other for market share, while also attempting to fend off the growing fast-casual category and the vastly increased ability of consumers to order meals for delivery from nearly every type of restaurant.

"Despite the changing landscape, our foot traffic analysis is proof positive that it's possible to build a dedicated fan base," according to the third annual Quick Service Restaurant Loyalty Index from Foursquare. The report uses actual restaurant traffic to show which chains are the most popular.

A person delivers Starbucks.

Starbucks has continually focused on the customer experience. Image source: Starbucks.

These are the most popular fast-food chains

Foursquare doesn't rely solely on how often people visit their favorite chains; instead, the location technology platform takes a deeper look using these four factors:

  • Frequency: How often do people visit?
  • Penetration: What percentage of people who visit QSRs visited the chain (this only applies in regions where a chain has locations).
  • Share of wallet: What is the median share "of each customer's total QSR visits to a particular chain over a year period."
  • Fanaticism threshold: How often would you have to visit a chain to be one of its top 1% of customers?

Based on those criteria, the 15 most-popular QSR chains are:

15. Taco Bell (Yum! Brands)

14. Bojangles' Famous Chicken 'n Biscuits

13. Burger King (Restaurant Brands International)

12. Jack in the Box

11. Hardees (CKE Restaurants)

10. Domino's Pizza

9. Tim Horton's (Restaurant Brands International)

8. Whataburger

7. Dairy Queen (Berkshire Hathaway)

6. Chick-fil-A

5. Subway

4. Sonic

3. Dunkin'

2. McDonald's

1. Starbucks (NASDAQ: SBUX)

Dairy Queen was the biggest mover on the list, rising 14 spots from last year. Burger King also had a relatively large jump, climbing four places to enter the top 15. Starbucks has now topped the ranks for three straight years, while McDonald's and Dunkin' switched places on the medal podium.

What does this tell us about loyalty?

"It's not all about burgers and fries -- the top ten QSRs show significant variety in terms of menu focus," according to the Foursquare report. "Brands topping the list include a coffee chain, burger joint, chicken spot, sandwich shop, taco joint, and pizza place. It's safe to say there's no one recipe for success when it comes to customers' loyalty to QSRs."

Starbucks consistently high marks reflect just how important it is to focus on the customer experience. The chain was a pioneer when it came to integrating digital technology into its stores, including a mobile ordering and payment app that has changed how customers interact with the chain for the better.

At Dunkin', the strategy on that front has essentially been to watch what its rival does, then copy whatever works. McDonald's hasn't done exactly that, but it too has focused on modernizing its stores, making it easier and faster to order, and improving the customer experience overall.

While tasty food helps build customer loyalty, what may be just as vital is better serving the people who walk through the doors, and removing as many pain points as possible from the fast-food experience.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.