Wal-Mart Stores, Inc. (NYSE: WMT) made a splash in recent years by opening health clinics in its Supercenter locations to give those who could not afford medical insurance a cheap way to get medical services. As always, though, the retailer hoped that those who visited in-store clinics would hang around and do some shopping as well.

In 2008, retail clinics have seemed to shut their doors in states like New York, Nevada and Indiana. Overall, 69 clinics in 15 states have given up the ghost, including those located inside Wal-Mart stores.

What's going on here? Is the strategy backfiring? Even one of the largest proponents of in-store retailer clinics, CVS Caremark Corp. (NYSE: CVS), indicated that it is slowing down its retail in-store clinic plans.

The reasoning here is plain and simple: the break-even does not come nearly as fast as most retailer in-store clinic operators would like. It takes a minimum critical mass of patients to get a profit in the bank, and even though Wal-Mart generates more retail traffic than any other company, its shoppers are just not visiting those clinics at a pace to make business plans work.

So it's impatience at work, not unlike quarterly numbers-obsessed Wall Street in a way. But Wal-Mart isn't giving up: it still plans on 400 co-branded in-store clinics by 2010 with marketing names of major hospitals for each location. It's built-in marketing for the market, saving Wal-Mart from having to create awareness or spend advertising dollars.