While there are a few exceptions, most TV shows have a natural shelf-life, writes columnist Elliot Furniss.

East Anglian Daily Times: Is X-Factor past its best?Is X-Factor past its best?

Either the zeitgeist they have captured fades away, or people simply get bored with the format.

A couple of the best examples include millennial monster hits Big Brother and Who Wants to be a Millionaire?

BB seemed to lose its relevance a couple of years before it made the fatal move to Channel 5, after which it seemed to become simply a flame towards which increasingly publicity-hungry moths would fly.

It had always been a haven for the wannabe celeb, but things went (even further) downhill after the channel change.

It’s now become a bit of a parody of itself and the viewing figures reflect just that. The most recent (16th) series on Channel 5 attracted an average of 1.4million viewers – fewer than half of those that tuned in to the last series on Channel 4 (the 11th), and even that was half of the 5.8m average viewers the show’s third series, won by Kate Lawler, drew in.

But once upon a time it seemed like the goings on in the BB house were at the forefront of the national consciousness. The tabloids were obsessed, there were tie-in books, compilation videos (yes, videos), spin-off CD singles of the remixed theme tune, board games, CD Rom games – you name it, you could buy a BB version of it.

And then there’s Who Wants to be a Millionaire?

The Tarrant-created titan of pre-2000 was essential viewing, or at least it was whipped up to feel that way by an eager media.

East Anglian Daily Times: Does anybody watch Big Brother anymore?Does anybody watch Big Brother anymore? (Image: This picture may be used solely for Channel 4 programme publicity purposes in connection with the current broadcast of the pr...)

I think the name of Judith Keppel will be one of the easiest pub quiz answers for years to come, and the “do you want to use a lifeline” gags will be used long after the show is fully forgotten.

But when the axe finally fell last year, it was well overdue. There were well over 500 episodes of the show, which at one time was more of a TV “event” than a gameshow but eventually became packed with cliché. It says something that arguably the most memorable moment was when someone was caught cheating.

So which of our popular shows are reaching their “best before date” – and what does the future hold for them? I think Strictly Come Dancing, despite what some may say, is still in rude health.

The departure of Sir Bruce was timed well and the presenting duo of Tess Daley and Claudia Winkleman are pretty solid, while the judging panel manage to deliver the goods.

It may well have peaked in popularity and quality, but the viewers are still sticking with it in their droves and as long as there is a steady supply of watchable celebs willing to take part/revive their careers, it’ll be pretty safe for years to come.

The other big beast of Saturday night TV has a slightly less certain future. This upcoming 12th run of The X Factor has an air of “last roll of the dice” about it.

The new presenting team (a welcome return from Strictly winner and former Xtra Factor host Caroline Flack and pop star/X Factor alumni Olly Murs) is a step in the right direction, while adding new faces such as Nick Grimshaw and Rita Ora to the panel helps make it feel more current – at least more so than having Louis Walsh and Mel B sitting in judgement.

But last year’s viewing figures were nearly 6m down on the 2011 series, which was won by Little Mix. Back then, the show seemed like it could do no wrong, fresh from unleashing One Direction on the world a year before.

East Anglian Daily Times: The Great British Bake Off is still at the peak of its powers.The Great British Bake Off is still at the peak of its powers. (Image: WARNING: Use of this copyright image is subject to the terms of use of BBC Pictures' Digital Picture Service (BBC Pictures) a...)

But arguably Little Mix are the only actual winners to have made it really big (the likes of 1D and JLS didn’t actually win the public vote at the time) and there’s only so long a show that claims to be a true talent search can keep turning out dud champions – can you even remember who won last year? (Answer: Ben Haenow. Yeah, no idea.)

Another big show returns this week, with Mel and Sue heading into The Great British Bake Off tent with another dozen cooks, accompanied, as ever, by judges Paul Hollywood and Mary Berry.

Maybe it’s the gentle and positive nature of the show, or the quality of the BBC production and contestant selection, or maybe it’s because, at just 10 weeks it’s refreshingly brief, but again, this format – now entering its sixth season – remains relevant and, I reckon, has a pretty tasty future.

What do you think? Email me at elliot.furniss@archant.co.uk or follow me on Twitter @Elliot_Furniss