Subway is bowing out of the breakfast fast-food market.

The world's largest fast-food chain, famous for its $5 foot-long sandwiches, has begun to let franchisees opt out of selling breakfast at their locations, according to a recent Bloomberg report. Increased competition, staffing issues and just a sheer lack of interest in breakfast options at some locations were a few of the factors that contributed to the decision.

Subway's endeavor into the breakfast market started eight years ago in 2010 when the chain began offering different egg-based sandwiches, hot coffee and early store hours that would make it more accessible for morning commuters. According to the report, however, the company has realized customer interest is not there.

A survey from market-research firm Field Agent found that 43% of Subway's customers do not eat at the chain for breakfast and 19% did not even know breakfast was offered, according to Bloomberg's report.

Subway is not the first fast-food chain to struggle to break into breakfast. A few chains like McDonald's Corp. (MCD) - Get Report and Starbucks Corp.  (SBUX) - Get Report have a corner on the market, making it difficult for other companies to carve out space for themselves to make a profit. Consumer preferences also play a huge factor as morning traffic for fast-food companies has slowed over the years, according to a study from The NPD Group.

Here are a couple of more fast-food chains that have missed the mark with breakfast.

Wendy's Co.  (WEN) - Get Report  has attempted to break into the breakfast market a few times now, with its first foray into fast-food breakfast coming in the mid-80s. That experiment lasted nine months before Dave Thomas, the late founder of Wendy's, realized his made-to-order breakfast options could not keep pace with the process of other fast-food chains. Some stores continued to serve breakfast, but the Wendy's push to enter the national market never came to fruition.

Wendy's most recent attempt at a national breakfast roll-out occurred in 2012 but was shelved within the year. 

Former Wendy's CEO Emil Brolick said in a 2014 interview that implementing a breakfast menu at the time would have been too costly to day-to-day operations and would detract from the quality of its other products, but left the question open if one of the country's most recognizable fast-food chains would ever serve breakfast nationally in the future.

Chipotle Mexican Grill Inc. (CMG) - Get Report  has been a leader in the fast-casual trend that has customers scrambling to eat at the chain for its burritos and bowls, but those customers will have to go elsewhere to get there breakfast burrito fix for the time being.

Chipotle would seem to fill a perfect breakfast niche — a fast-food chain that actually makes tasty burritos and requires employees to come to work hours before stores open — that could seamlessly add breakfast burritos to its menu. Unfortunately, that reality hasn't happened yet as the company has made no inclination to rush into the breakfast market.

The marriage between breakfast and Chipotle has had some rough patches. The company tested breakfast options in two of its stores at Baltimore-Washington International Airport and Dulles International Airport back in 2013 but with little success. Both stores offered a breakfast bowl, burrito and tacos with more traditional morning food staples like scrambled eggs, crispy herbed potatoes and chorizo. 

The results from those tests came back that people were still electing to order their regular Chipotle orders, which led to the company discontinuing further tests, according to what spokesperson Danielle Winslow told Business Insider at the time.

But breakfast could be on the horizon for Chipotle after it hired away former Taco Bell CEO Brian Niccol back in February. Niccol was responsible for launching Taco Bell's breakfast menu that has become a popular option among consumers.