As a result, this week's Friday Fiver picks a quintet of characters whose time spent on our screens was far too brief - those TV figures who were cut off in their prime, with so much potential left unexplored...
Sgt. James Doakes (Erik King) - from Dexter (2006-2007)
The problem with Doakes was that he was just too much of a bad-ass. While it took Deb (Jennifer Carpenter) six seasons to stumble onto her brother Dexter's devious actions, Doakes had his suspicious eye on our anti-hero from day one...
By the time season two came around, Doakes had discovered that Dexter (Michael C Hall) was the notorious Bay Harbour Butcher, but this is Dex's show, so the far-too-efficient police sergeant had to be offed, dying in a massive gas explosion. We think the show misses him, even five years later.
Arthur Teller (Danny Glover) - from Touch (2012)
A recent addition to the ranks - Kiefer Sutherland's new drama was a bit of a mixed bag, but one of the strongest elements of the early episodes was Danny Glover's supporting turn as troubled professor Arthur Teller, a fitting foil for Sutherland's frantic father Martin Bohm.
Unfortunately, Teller was killed off in mysterious circumstances at the end of the sixth episode. It's a real shame - if you land Lethal Weapon star Glover, you should hang onto him for as long as possible.
Doyle (Glenn Quinn) from Angel (1999)
The various different variations of the Angel cast each have their own fans, but one of our favourites was the original lineup of Angel (David Boreanaz), Cordelia (Charisma Carpenter) and charming Irish demon Doyle (Glenn Quinn).
Several reasons have been put forward as to why the character was written out after just nine episodes, but whatever the truth is, it doesn't change the fact that Glenn Quinn was an intensely charismatic performer and that Doyle was a fantastic character who deserved a longer run.
That said, the character's exit in the fantastic episode 'Hero' is as moving a piece of TV as you're ever likely to see - one made all the more affecting by Quinn's tragic real-life passing in 2002.
The Ninth Doctor (Christopher Eccleston) on Doctor Who (2005)
Sure, we all loved David Tennant's cheeky chappie take on the Time Lord, but it would've been nice for acting legend Eccleston to remain in the role for more than just a single 13-episode run. As is often the case, various reasons have been mooted for his swift departure, but Chris insists that his "conscience is clear"...
Oh, and an honorary mention too for Eccleston's predecessor Paul McGann, who - as the Eighth Doctor - only took up the Who reins for a single TV movie in 1996. Forget cut off in his prime - poor Paul never even got a fair crack at the whip.
Mr. Eko (Adewale Akinnuoye-Agbaje) from Lost (2005-2006)
Everyone had their favourite character on Lost but one of our faves was the impossibly cool Mr Eko, played by Brit actor Akinnuoye-Agbaje. The mysterious criminal-turned-holy man appeared in just 19 episodes before he was cruelly snatched away by the smoke monster - so much untapped potential wasted...
To rub salt into the wound, Eko was one of the few Lost characters not to return in some form for the series finale - rumour has it that Akinnuoye-Agbaje and the show's producers couldn't agree on a fee. But it was the fans that paid the price.
Which TV characters do you wish had stuck around longer? Name your picks below!