Not paying taxes will do it for sure. We also had a small chain of successful restaurants in the Tampa area that was expanding at a rapid pace...sometimes buying out others to re-brand. Then a group of them closed at once....which turned out to be tied to the owner's drug addiction. Apparently he was using several of the stores to finance his habit like a private piggy bank.
The other franchises owned/operated by other family members are still open.
I would venture to say that most businesses don't fail due to lack of expertise in the service industry (PC repair, Lan Center, Restaurant, Auto Shop, etc) or even customer demand...most likely fail because of insufficient planning, funding, or mismanagement of the resources and liabilities.