Walmart (WMT) bills itself as a company that sells goods at the lowest prices but the empire was really built on controlling costs.

Founder Sam Walton built massive, inexpensively constructed stores in rural areas where the land was cheap. To fill those stores he bought from vendors in bulk quantities, demanding that they give him discounts. The vendors were happy to comply because they knew Walton would come back with more huge orders.

With the money Walton saved by wringing the costs out of the system he was able to charge customers less. The customers were happy to drive a little farther to get the better deals. "Mom and Pop" local small town merchants may be romanticized but the truth is everyone wants to a bargain and Walmart had better prices.

With this formula Walmart has grown beyond anyone's wildest dreams. In 51 years Walmart has grown into the greatest force in retail the world has ever known. Last year the company had revenues of $470 billion. That works out to $1.3 billion every day. In the time it will takes to watch the attached clip, Walmart will book more than $150 million in sales.

Walmart now employs more than 2 million people, by far the most of any company and behind only the U.S. Department of Defense, the Chinese Army, and China's state owned railway system.

Related: Too Big to Succeed – It’s Time to Break-up Walmart: Sozzi

Not all of those employees are happy. Walmart has been dogged by charges of unfair labor practices for years. The tales of alleged abuse are legendary including multiple charges of locking employees in the stores overnight to clean. In some cases those workers have proven to be illegal immigrants.

As the company has grown so has resentment. The vendors who once so happily accepted Walton's huge orders now complain that the company has monopoly-like power over them. Small town residents love the low prices but local merchants have been put out of work.

Some of the allegations are fair and others are simply backlash against the company's success. Either way growth has slowed to a crawl and international expansion efforts are meeting stiff resistance.

Like every empire to come before it, Walmart (WMT) is beginning to rot from the inside out. It may appear to be rolling but under the surface the Walmart empire is in rapid decline.

Here are three of the dozens of headwinds the company is facing:

1. The stores are a mess



The average Walmart store takes up more than four acres of land. The Walmart protest website MakingChangeatWalmart.org says the company's Supercenter stores occupy 20 to 30 acres of land, including the parking lot.

Retail is a game of endless upkeep. Clothing racks, bathrooms, produce sections and an endless number pegs holding things like batteries and socks all require constant attention. Even with an unlimited budget for maintenance keeping a store the size of four football fields would be a challenge.

Walmart's dedication to cost control often comes at the expense of basic upkeep. Store managers, forced to keep expenses at a minimum per Walmart tradition occasionally go rogue and get lax on hiring and labor practices in the name of saving a few bucks.

Walmart has a well-earned reputation for being rundown with poor displays and empty, mislabeled shelves. Dirty stores are an insult to customers. Sloppy shelves imply a fundamental lack of respect.

When the only competition was a hodgepodge of inefficient local stores with much higher prices, customers were willing to suffer a little abuse. Now that companies like Family Dollar (FDO) have closed the price gap it's becoming apparent that shoppers prefer to spend their money in tidier, less confusing places when given the choice.

Brian Sozzi of Belus Capital Advisors says it's going to be all but impossible for Walmart to revamp the stores on the fly. "It takes 10 days to update a Family Dollar," Sozzi notes. "To update a Walmart it can take months."

2. The Walmart business model doesn't translate



Reuters is reporting that Walmart might make a bid for Chinese grocer ParknShop. If they do, they would finally get a foothold into China. International growth has been one of Walmart's biggest challenges.

With the U.S. market largely saturated, Walmart has occasionally resorted to underhanded methods to achieve international growth. Last year The New York Times ran a series of articles detailing bribery attempts by Walmart in Mexico and their plans to build stores on ancient ruins.

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