The franchise has limited offerings. Many great businesses have thrived because they do one thing well, but a one-trick pony is most vulnerable to consumers’ whims. “I’d be reluctant to buy any franchise that’s focused on a single product” or service, says Bond. That’s a big reason why meal-prep kitchen flopped; in recent years, ink-cartridge stores have also suffered because of a singular focus.

The owners are rookies. Franchise companies are often born with a novel business idea that gets packaged and sold before the operators prove their broader business acumen. “That’s why we always look at management strength and history before we work with a franchise,” says Bingham. If they have vision — and capital — they will know how to tweak the business model to change with the times. If their experience is limited to a single widget or service, however, they may flounder and flop.

The growth can be described as “too much too soon.” As with any bubble, whether it’s home values or gourmet hamburgers, a sudden boom in the market is always a warning sign, says Stephen Schwanz, president of Scottsdale, Ariz.-based Franchise Capital Advisors. Case in point: self-serve yogurt franchises. “Many of these places are doing really well, but there are probably five or six of them within a mile radius of where I’m sitting,” he says. It doesn’t mean the whole segment is doomed to fail, he adds, but it does mean franchisees need to be extra diligent about picking the right flavor.

The franchise’s product or service isn’t a necessity: “I’m leery of ideas that rely on discretionary income, especially in this economy,” says Bond. If a franchise is focused on a discretionary product or service, investigate why your customers will keep spending even when times are tough. Notable exceptions include fitness franchises, which have held up relatively well in a tough economy, as well as franchises related to caring for seniors, educating kids and pampering dogs. “Every parent wants to get his kid into Harvard,” says Bond. “And people without kids seem to lavish attention on their pets no matter what it costs.”