Ever since the rise of John, Paul, George and Ringo in the early '60s, there's something about bands that we've all fallen in love with.
Music that comes from a group, as opposed to something produced by someone going solo, just has a different feel to it. There are dynamics and energies that come through in songs that could have only emerged because of the time a band as spent together, and the psychic-like understanding they carve out.
Personalities start to become more recognisable and we, as fans, come to know a band's lineup on a level that we usually reserve for family members or close friends.
However, the cut-throat world of music has shown time and time again that it rarely remains like that for as long as we would like. Being such a creative passion, ideas and feelings about styles or direction have constantly led to arguments among band members and broken up even the most successful of groups.
Sometimes, great rock bands lose a key member, but still manage to churn out the hits without them...