You’ve probably heard of the famous Leaning Tower of Pisa in Italy, but have you heard of the leaning tower of San Francisco? It’s called the Millennium Tower. Built in 2008, this 58-story skyscraper stands proudly—but slightly crookedly—in downtown San Francisco.

The problem? Its engineers didn’t dig a deep enough foundation. So now they’re being forced to retrofit the foundation with repairs that may cost more than the entire tower did when it was originally built—a fix that some believe is necessary to keep it from collapsing during an earthquake.

The painful lesson here? Foundations matter. When your foundation isn’t solid, catastrophe…