Why do jimmy fallon and Conan have the microphones on the desks when they have the microphones on their shirts?

jimmy fallon and Conan O'Brien keep microphones on their desks as a backup and for added audio clarity during their shows. The desk mics can pick up ambient sounds and enhance the overall sound quality, ensuring that viewers get the best experience. Additionally, having both types of microphones allows for flexibility in movement and interaction during segments.