Last-minute flights are often expensive due to a combination of factors including supply and demand dynamics, airline revenue management strategies, and the urgency of travel plans. Airlines anticipate that travelers booking close to the departure date have a high necessity to fly and are willing to pay a premium. Additionally, there are fewer available seats as the departure date approaches, allowing airlines to charge higher prices. The lack of flexibility and increased operational costs for airlines to accommodate last-minute bookings also contribute to the elevated prices. Understanding these factors can help travelers make more cost-effective travel decisions.