We don't fly east from India to the USA primarily due to the Earth's rotation and the jet streams that impact flight paths and fuel efficiency. The Earth rotates from west to east, and jet streams, which are strong air currents, also flow from west to east. So, flying westward from India to the USA is faster and more fuel-efficient due to these natural phenomena. Also, it's safer to follow these established routes to avoid areas of turbulence and bad weather. Taking the western route also allows pilots to make emergency landings if needed, as it's populated with many airports.