Why was the colonial capital moved from Antigua Guatemala to Guatemala City in 1773?

The colonial capital was moved from Antigua Guatemala to Guatemala City following the devastating Santa Marta earthquakes of 1773.12

These powerful tremors leveled many of the city's buildings, including those designed to withstand seismic activity, and resulted in significant loss of life. In the aftermath of this destruction, Spanish officials determined that the site was no longer suitable for the administrative center of the captaincy general and chose to relocate the capital to a safer location approximately 28 miles (45 kilometers) to the east. The new capital, formally established in 1776 as Nueva Guatemala de la Asunción, was intended to provide a more secure environment for the region's government.13