What Factors Cause The US’ Busiest Single Runway Airport To Execute Reverse Ops?

The busiest single-runway airport in the United States, undoubtedly, is San Diego International Airport (SAN). Located near the southern border of California and serving the cities of both San Diego (United States of America) and Tijuana (Mexico), the airport is renowned for its central location and pan-American and growing international network. However, what causes aircraft arriving and departing at the busy airport to flip their arrival or departing directions?