When French retailer Carrefour and U.S.-based Costco Wholesale Corp. opened their outlets in Makuhari, Chiba Prefecture, a year ago, many saw the foreign stores as a threat to domestic supermarkets.

One year later, however, the newcomers seem to be having a hard time meeting local customer needs.

But the foreign retailers should not be underestimated, analysts said, as they are flexible, can adapt and have a strong financial base.