While some pop acts succumb to temptation and hit the road again others do not. The Beatles kept the world guessing for a decade, but wisely decided not to bow to popular pressure until fate quashed the rumours forever.
Look at ABBA. Should the Swedish super group ever reform it would be the biggest news in pop history. Ain't gonna happen. Benny, Bjorn and the girls know they had something special which was of its time, the magic of a moment.
Times winged chariot stops for nobody, not even pop superstars. And it most certainly does not stop for comic characters, all of which brings me somewhat witheringly to Alan Partridge, a character absent from television for almost 20 years and one whose sheer crassness had the power to make an audience squirm.
Yes, he's back. Following what can only be described as an ill-judged venture onto the big screen (Papa Alpha - oh dear, oh dear) Steve Coogan's decision to resurrect his alter ego Alan Partridge seems particularly baffling. The film flopped and was rightly panned by the critics. So, why? There can only be two explanations: money or more likelier, the desperate act of a broadcaster running out of ideas . . .
Partridge riding shotgun to a bright and breezy female co-presenter as guest host of a magazine programme (The One Show?) probably looked a good idea - on paper. Her slick professionalism playing against his shambolic amateurism however never does ring true. It all feels a trifle forced. The humour - such as it is - is so pregnant it almost groans under its own weight. There's no surprises at all here, just a medley of greatest hits. Yawn.
And so an age-defying Coogan sits on the studio sofa putting his foot into just about anything and everything. Sassy female co-presenter meanwhile comes to the rescue of the always bewildered, very ring-rusty Partridge. And that, boyz n girlz, is just about it. The laughs are few and far between. Even the VTs which provide a welcome relief from the magazine format fall flat on their face.
Frankly, the longer this goes on, the more painful it becomes. It all feels rather forced, a forlorn attempt to capture the energy and vitality of previous gigs but one from which the magic formula has long since vanished.
After watching the first instalment of This Time with Alan Partridge there can be little doubt that though cold hard cash must have played a role somewhere, this was ultimately an act of desperation, a distress signal from the BBC.
For those unable to catch this or unwilling to, think Muhammad Ali. Not the strutting Ali of his prime, but the stumbling rather inept Ali tempted back into the ring in the late 70s only to discover the world of boxing had moved on in the interim period. Watching Steve Coogan reprise this role was rather like watching the once great Ali, a shadow of his former self, surviving on instinct alone.
Whereas throwing in the towel is always a viable option in the boxing ring, no such nuclear option exists in the world of the television sit-com. And so it trudges on for a full 30 minutes. But that's not all. There's more of this - two more helpings. Groan.
Perhaps it's just indicative of how far BBC comedy has fallen that the corporation went with this Lazarus strategy, raising the dead. Fawlty, Blackadder, Ab-Fab, Dad's Army, David Brent . . . when did the corporation last have genuine comedy gold on its hands?