The Kmart store in my neighborhood closed last weekend. Now there’s a giant empty space in the Spirit Valley Mall in West Duluth, with a faded area above the doors where a sign once read: “Big Kmart.”

It took more than 30 years for the store to run itself out of business, and I’d probably need a degree in finance and a long look inside the books of parent company Sears Holdings Corporation to ever understand. How does a neighborhood’s only department store — a place that’s known for always having lines at the cash registers — go out of business?

The answer to that question might be that retail stores are struggling in general, and any store with massive overhead costs that provides a lousy shopping experience doesn’t stand a chance. And the West Duluth Kmart was a lousy shopping experience.

The lines at Kmart perhaps weren’t due to the high volume of traffic, but instead the understaffing at the store. Target or Wal-Mart might have a dozen checkouts open at once; Kmart seldom had more than two.