By the Mike Love Factor, I am referring to a member of the band who plays a limited role in a music group's direction, song writing, and success, potentially runs in opposition to the group direction despite success with that direction, but who nonetheless forms a massive ego which creates problems with other members of and outside of the group. At such point, that member begins to assume authority within the group, in conjunction with distraction, personal issues and/or waning interest from the other members and original leader(s), takes it over, potentially expels the original members, and turns the group away from it's direction at best, and at worst turns the group into a tribute act to it's own early discography and iconography.
In a cynical and uninformed view, some have interpreted Paul McCartney as the Mike Love Factor for the Beatles. However, such is not the case. I have drawn the analogy that it would be something like Ringo Starr growing a massive ego, becoming angry and jaded at his band members for their success and acclaim, and retroactively claiming that his contribution was massive and he was the true artist. And at such point, such as right after "Abbey Road", taking over from the other members, gradually replacing the others with a slew of rotating session musicians, putting them and himself in mop top wigs and Beatle boots, and having them play only the hits of 1964 to 1966 at every state fair and Seaworld grand opening they could attend to an aging but loyal audience. And casting that as the Beatles, and releasing a slew of albums that attempt to replicate the sound of the early Beatles to increasingly dwindling sales, plummeting critical claim, and increasingly limited public interest. And then speaking constantly about his own glory, suing the other original Beatles, lashing out at ex-wives and other musicians, and otherwise being a jerk. You can play with this on any band, from the Rolling Stones to Led Zeppelin. And indeed, outside of a jerk member, it is that factor which a lot of 60s acts have fallen into, which is only one or two original members remaining (if any; sometimes the rotations and replacements mean no one from the beginning is left and it keeps rotating) and playing a bunch of forgotten greatest hits to an audience of grandmothers. This discussion can also focus on that factor instead, with bands that did not go that direction actually going that direction.