Why McDonald's doesn't serve breakfast all day

McDonald's breakfast notoriously ends at 10:30 a.m. at most locations. After years of public outcr…

McDonald's breakfast notoriously ends at 10:30 a.m. at most locations.

After years of public outcry, the brand has started offering some items after midnight. CEO Don Thompson also said that the fast food giant was flirting with the idea of all-day breakfast.

We reached out to an expert, Scott Hume at BurgerBusiness.com, to find out why McDonald's hasn't fully capitalized on the breakfast menu's popularity.

Limitations in the kitchen hold the brand back, Hume told Business Insider.

"It's a shock to hear, but McDonald's doesn't do made-to-order breakfast," Hume said. "Its customer traffic is too great for that. So eggs and sausage are pre-cooked and held for breakfast sandwich assembly."

At 10:30, McDonald's needs to start using its toasters and grills for burgers, chicken nuggets, and sandwich buns instead, Hume said.

J.M. Owens, a McDonald's operator in Atlanta, explained more about the process to BurgerBusiness.com earlier this year: "First, there are some capacity issues. We only have so much toaster space and so much grill space. Unlike a lot of breakfast QSRs, we still cook our product on a grill. Many of the pretenders are doing a ton of prep in microwaves. For instance, go into a Dunkin’ Donuts or a Starbucks, who are chasing breakfast, and you don’t find a grill, or oven, or fryer. We prefer to be a restaurant rather than processing everything through a microwave."

"The 'McDonald's After Midnight' menu works when customer traffic is light," Hume told us. "But it wouldn't work all day because it requires streamlining both breakfast and burger menus to a few all-star items."

So, it could take a long time for McDonald's to figure out a way to do breakfast and burgers together.