Suffice it to say McDonald’s all-day breakfast was a hit. The fast food chain, which struggled mightily from the end of 2013 through mid-2015, got a huge boost when it introduced an all-day breakfast menu last September, helping push a 5.7% same-store sales growth in the U.S. during the fourth quarter of 2015.

Surprising as it is, customers weren’t entirely happy with the change because the all-day breakfast menu is limited to a select few items.

Weighing franchise needs with customer wants

The main reason behind a limited all-day breakfast menu is to make the transition easier on franchisees. These small business owners, which make up more than 80% of McDonald’s restaurants, are the ones who bear the brunt of the costs of adding breakfast to the menu for the full day.

For many franchises, this included ordering new equipment, increasing hours and possibly even hiring new workers to keep up with the demand, keep wait times low and have enough room to keep up with the full menu items — for example, employees can’t grill burgers and sausage on the same grill it cooks eggs.

In most cases, franchises were forced to take on these extra costs up front with no promise that an all-day breakfast menu would actually increase foot traffic in their restaurants. So far, however, it turns out that things have gone well for McDonald’s U.S. locations.

McDonald’s choosing the customer

As exciting as all-day breakfast has been for customers who prefer a sausage, egg and cheese biscuit over a quarter pounder with cheese, the number one complaint is that the selection is limited.

“Many customers are frustrated about the limited menu,” one franchisee wrote in response to a recent survey by Nomura analyst Mark Kalinowski. “I am in a McMuffin market that was almost evenly split, and I have customers furious that they cannot get biscuits. They feel that it is a sham or false advertising.”