never was this more graphically demonstrated than with All About Eve's performance of Martha's Harbour on TOTP in 1988, when Julianne Regan completely lost her starting point......
It also helps you to sing in tune. Rather than having to try and compete with music bouncing off the walls around you, if you can hear yourself directly in your ear it really makes a difference. This is also why some people stick their finger in their ear when they sing
In-ear monitors provide a better service than standard stage monitors because the sound can be individually mixed to suit the musician or vocalist. Some singers like to hear the whole band,. some just like guitars, and so on, and drummers in particular can mix their drum sound in with the band through in-ears, which double as defenders from the noise they make.