The article discusses how buildings can be strengthened to better withstand earthquakes. Researchers studied retrofitted buildings in China and Mexico to see how well they performed during earthquakes. They used computer simulations to analyze the effectiveness of different strengthening methods. The results showed that choosing the right retrofitting system is crucial for improving a building's seismic performance. It's important to optimize the overall performance of a retrofitted building, not just repair it. Keeping the weight increase low is key to a successful retrofit solution, as heavy additions can reduce effectiveness. Some retrofitting methods may actually make a building more vulnerable to earthquakes if they increase its weight too much.