The airline promotions also depend on the destination and origin of the flight. Weekly ticket demand varies depending on whether the place is a metro city, or a tourist destination.
For example, many people will fly between Delhi and Mumbai during the weekdays because many important government offices are located in Delhi, increasing the ticket rates. However for holiday spots like goa , most people will visit mainly only on a weekend or holiday, as they do not wish to take leave from their office, as most organizations allow a limited number of holidays for their employees.
So the ticket prices are higher for flights to goa on Friday and from Goa on Sunday, Monday. On other weekdays, airlines are offering promotions and discounted fares as few are travelling to goa