When is it time for a popular TV show to come to an end?

If the show is still getting good ratings, the network might not want to lose a hit. But fans could counter that the quality has deteriorated over time. Another reason for a show to end is if the star leaves the show and it naturally has to end with them (as will likely be the case with 'Two and a Half Men').

All of those scenarios are covered in this list of five shows that are still popular but probably should end this season anyway. Now, all of these shows won't be ending this season -- in fact, all but one have been renewed -- but from a pure storytelling viewpoint, it might be time for them to be over.

This is a list we do in some form every year, but with the upfronts in a few months and pilot season, it's worth another look.

1. 'CSI'/'Criminal Minds.' Yes, the first entry is actually two shows, because they're pretty much interchangeable.

Sure, it's easy to figure out which one is which (for example, 'CSI' uses a song by The Who), but they still follow the same formula and pattern. CBS has a lock on this type of formula -- the intros, the way the murder is shown, how the carefully-crafted cast of quirky characters investigate the crimes -- using it for all of their procedurals, but at least there's still freshness and character development in 'The Mentalist' and 'NCIS.' 'CSI' and 'Criminal Minds' just seem to go more for the flash and the gore.

It's not like they haven't been on for years. 'CSI' is in its eleventh season and 'Criminal Minds' is in its sixth. Both have produced spinoffs that seem more like brand extensions than different, quality shows. Hey, when 'Rhoda' spun-off from 'The Mary Tyler Moore Show,' they didn't call it 'The Mary Tyler Moore Show: New York.'

Take a look at this promo. Everything they try to tell us is a positive thing for the show -- all of the different cases the team has had over the years -- actually just shines a light on how they've run out of ideas:




But relax fans. Both of these shows still get good ratings so they're not going anywhere. In fact, 'Criminal Minds: Suspect Behavior' seems to be a hit, too, even if the ratings for episode 2 did drop 24 percent. But most critics are going to put it on their "worst" list for the year (and it's only February).


2. 'Desperate Housewives.' There has always been a lot of silliness on 'Desperate Housewives' along with all of the murders and mysteries, but it has become too silly in recent years. Even viewers who were die-hard fans the first three seasons are saying, "Wow, is that show still on?"

The writers seem to be straining to come up with a new crazy situation for Susan or a new neighbor to squeeze into the show. They've killed off Edie and aged the twins and had things explode and more storylines you would expect from a soap opera. Heck, I wouldn't be that surprised to see a spaceship crash on Wisteria Lane, with all the neighbors wondering if they can deal with robots from another galaxy living next door. The aliens could take the form of a hunky actor or bombshell actress, maybe have an affair with one of the housewives and get her pregnant. Sweeptastic!


3. 'The Office.' It sounds simplistic to say that Steve Carell leaving 'The Office' would have made for a great opportunity to end the show, but Steve Carell leaving 'The Office' would have made for a great opportunity to end the show.

Let's face it, hasn't the show been getting a little ridiculous? Especially the fact that this documentary crew is still filming at Dunder-Mifflin after all these years? Not even Ken Burns has ever done anything this extensive.

There's been talk about who will replace Carell. Everyone from Danny McBride to Harvey Keitel to Ricky Gervais has been mentioned, along with people still in the office like Rainn Wilson or Zach Woods. But wouldn't that make it seem like the show is really pushing things too far? Sure, it's all in the writing, but it has had a good seven-year run, and it just "feels" right that the show should end. 'Threat Level Midnight' demonstrated that Michael Scott has grown up -- he'll probably even ride off into the sunset with Holly. Wouldn't that be a nice send-off for the entire series?


4. 'Burn Notice.' How many seasons can a show about a spy trapped in one city go on before it starts to become a little too formulaic and safe? Turns out it's about five.

'Burn Notice' is still a good show, but that formula -- Michael has to save yet another "victim of the week" while still trying to find out who burned him -- has become a bit tedious. How can the show shake things up? Have Michael actually find out who burned him -- the real Big Kahuna who is truly the top person -- and end that plot for good. Then he could either become a spy again and go on official missions (insisting that Sam and Fiona be on his "team," of course) or he could decide give up that game and continue to help people as a troubleshooter/private eye. (The prequel movie will be a nice change of pace though.)

Either way he has to get out of Miami, at least once in a while. It'd be great to see Michael and Sam and Fiona on missions in New York City or Paris -- let's make that happen.


5. 'Chuck.' This is the last entry on this list for two reasons. One is because, unlike the above shows, 'Chuck' could still have a lot of stories left to tell. And two ... well, it's my favorite of the shows on this list.

Like 'Burn Notice,' another show about spies, 'Chuck' is in danger of repeating itself, if they haven't already. It's been very impressive to see how 'Chuck' has grown over the seasons. Not the character of Chuck (though he has grown, too), but the show itself.

'Chuck' has avoided getting stale so far by changing things up. A lot of shows would have kept the Morgan character in the dark for the entire run of the series, so it made you smile when he finally found out about Chuck's secret life and actually became part of the team.

A lot of shows would have kept Awesome as the goofy brother-in-law who didn't know anything, but the writers actually made him find out about Chuck's double life, leading to some great plots involving Chuck's sister Ellie. This is one of those light adventure/comedy shows that has a lot of deeper things going on, and that's been great to experience.

But after several seasons, it's starting to feel a little unrealistic and thin. Chuck and Sarah having yet another argument? Casey threatening Morgan with a growl and a look again? The Buy More guys acting all creepy and odd?

How could they shake things up for a final season or two? Ditch the Buy More and the relationship stuff and focus only on the spy work. Make it a completely different show, with the gang battling Volkoff (an organization now headed by his daughter) one last, spectacular time.

Who knows how much longer the show can stay on the air anyway. Of the shows on this list, it's the only one that hasn't been renewed yet. It has always been on the bubble, with only online fans and submarine sandwich lovers saving it, but it looks like this could actually be the last season of the show. And if it is, that's OK. Chuck and Sarah are together, the mom has been found, Morgan has found someone, Casey has reunited with his daughter, the Buy More was rebuilt, and Awesome and Ellie have a baby.

That would be a great ending for any show, wouldn't it?


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