I am located very near to a base with a Sukhoi 30 squadron in India. The Indian Air Force jets keep doing these sorties every day and night. I have always wondered what exactly do these jets do during their sorties. I thought it was always about training. But I found out that the basic training for these pilots happen elsewhere. So what exactly happens on a normal day with these trained pilots and their jets?
As with any job, there will be some initial training to learn the basic skills needed, and that is typically done at a central location. But there will also be ongoing practice to maintain those skills and continue to improve them. Modern fighter jets are complicated machines and take a lot of knowledge and practice to operate. Simulators and classroom learning help but can't completely substitute flying and maintaining real aircraft. In the US, military aviators get about 20 hours per month of flying time. There's a saying in sports that "you play how you practice." When these pilots go into battle, lives are on the line, and they want to be able to recall skills they practiced recently, not years ago in basic training.
Recent training (proficiency) is an important facet of mission readiness. Basic training is important, however, it may be done in another country (Americans train partner countries in the US) and hopefully it is apparent that follow-up training is critical in the homeland.
What is not visible is the training that happens behind closed doors in simulators and the classroom.