While mostly known as a TV term, a spin-off is actually any sort of work of media that derives from another, without being a direct sequel or prequel. According to some, the first ever instance of this dates all the way back to the days of radio with a series known as The Great Gildersleeve from 1941, which spun off from Fibber McGee And Molly. As far as TV is concerned, while it might be debatable, The Andy Griffith show is fairly widely accepted as the first ever, or one of the first ever spin-off shows, coming off the heels of The Danny Thomas Show. Ok, history lesson and possible trivia question review over.

The concept of a spin-off is simple. Take a ing character from one show and move them into another. We would learn far more about them being the star of their own show than as a ing character in the original show. Or you can introduce a character or a set of characters in one episode and shoehorn them into the world of the show. This kind of spin-off is called a “Backdoor Pilot,” these characters aren’t meant to be a part of the main show, they’re just being introduced before they move to their own series.

No matter how we get them, there have been some great spin-offs over the years, some even suring the original. Others...not so much. Here are 15 Notoriously Bad TV Spinoffs Every Forgets (And 15 That Were Actually Worth Watching).

Bad: Joey (Friends)

Like a warm, comfy blanket, fans of Friends can cozy up to their favorite TV buddies and binge out on over 200 episodes of the nineties and early aughts staple. While every character had their moments over the years, no character could have benefited more from fleshing out than Joey Tribbiani.

So, when the series ended, Joey decided to get serious about his acting career and headed to Hollywood for his own show. While it lasted two seasons, those were two seasons of good-will viewership and not very strong ratings.

Worth Watching: Family Matters (Perfect Strangers)

As an elevator operator for the Chicago Chronicle on Perfect Strangers, Jo Marie Payton endeared herself enough to fans and writers to garner more stories involving her character. From the world of Perfect Strangers began Family Matters, which was one of the most endearing family sitcoms of the nineties.

Payton’s character was the gateway towards meeting Carl Winslow, played by Reginald VelJohnson. But most importantly, the show’s breakout star, the mega geeky and often fumbling, Urkel. The show actually outlasted both its predecessor and series’ star by one season. Judyann Elder took over the role for the show’s ninth and final season.

Bad: The Lone Gunmen (The X–Files)

The X-Files was to the nineties what Stranger Things is right now. The mix of monster-of-the-week shows, government conspiracies, alien coverups, and the chemistry between David Duchovny and Gillian Anderson made for a pop culture phenomenon. The series struggled towards the end of its original run, but they still tried to introduce a new spinoff series for The Lone Gunmen.

Centering around Mulder’s trio of conspiracy nuts, the show lasted only thirteen episodes. But it also helped to showcase a fundamental flaw around some ing character spin-off shows, the characters aren’t strong enough without the main series’ leads to carry their own show.

Worth Watching: Star Trek: The Next Generation (Star Trek: The Original Series)

It was nearly twenty years since the original Star Trek series ended when creator Gene Roddenberry created a new series for Trekkies young and old. It took a few years to find its footing and fanbase. But then Captain Piccard became one of the Borg in one of the most thrilling cliffhangers of all TV history.

Star Trek: The Next Generation not only helped update the franchise, but it extended it as well. Thanks to the popularity of the show, the original cast movies gave way to The Next Generation crew having a few cinematic turns. Fans also got Deep Space Nine, Voyager, and to a lesser extent, Enterprise. For over fifty years, Star Trek has captivated fans, but if TNG flopped, the entire franchise might have gone with it.

Bad: Law And Order: Trial By Jury (Law And Order)

For almost thirty years, the familiar two-note chime has been the hallmark of one of the most enduring police procedural shows and franchises TV ever saw. If someone tried to watch consecutively, you’d be watching all of the shows for nearly fifty days straight (and probably be a lament expert on the law in the process).

Sadly, thirteen of those hours would be to devoted to the clunker of the bunch – Trial By Jury. The show brought original series star Jerry Orbach back to the fold. Instead of focusing on the Order part of the show, it focused more on the preparation of trial lawyers. The idea didn’t go over well with viewers and was canceled for poor ratings.

Worth Watching: Law And Order: Special Victims Unit (Law And Order)

Now tied with its predecessor for total number of seasons, Special Victims Unit has sured the original in of popularity. For over a decade, the pair of Benson and Stabler were probably the most intense on TV. It took several more years after Christopher Meloni’s departure, but between a strong ing cast (stalwarts like Mariska Hargitay and Ice–T staying on as the rocks of the show), the series has had a resurgence this season.

Thanks to the addition of Chicago’s tough as nails ADA Peter Stone, and some more serialized storytelling, SVU has redefined the old term, “must see TV.” Hopefully, the trend continues into what should be a record-setting 21st season.

Bad: The Finder (Bones)

One of the key ingredients to creating a good spin-off is to do your best to keep the charms of the original product, enhance those charms while creating some new magic for fans to glom onto. The biggest problem with The Finder, the spin-off to Bones, is that a humongous part of the charm of Bones was its amazing ensemble cast.

That cast couldn’t come over to the new show every week. That’s a hard kind of magic to reproduce, even when utilizing the quirky detective trope and the talents of the late-great lovable bear that was Michael Clarke Duncan.

Worth Watching: NCIS (JAG)

It isn’t very often that a spin-off sures its predecessor to the level NCIS has done. Spinning out of the moderately popular JAG, NCIS has become a juggernaut of a show and franchise. It’s ratings nearly single-handedly help CBS maintain ratings dominance and it has launched two of its own successful spin-offs.

The show has been voted “America’s Favorite TV Show.” 16 seasons in and mostly in the top five ratings-wise with no signs of slowing down, it's hard to argue with the award.

Bad: Once Upon A Time In Wonderland (Once Upon A Time)

Disney had yet another veritable goldmine on its hands when ABC debuted Once Upon A Time to the world in 2011. Introducing classic and beloved Disney and other fairy tale characters in a new real-world setting was a big hit and was the only place we’d ever get to see all of these characters intermingling (nevermind Kingdom Hearts).

So why not try to catch lightning twice? The creative team behind Once tried to do it all again with Once Upon A Time In Wonderland. The spin-off has the unenviable task of trying to create its own mythology while interweaving in and out of its parent show’s own existing mythology. The idea to be a sequel, prequel, and side story all at the same time failed and was canceled after 13 episodes.

Worth Watching: Curb Your Enthusiasm (Seinfeld)

Curb Your Enthusiasm might not be a direct spin-off to Seinfeld, but it definitely is its spiritual successor. The format for both shows was devised by Larry David to have seemingly nothing going on in the not so mundane lives of these people. The original series is arguably the greatest sitcom of all time.

Being on HBO allowed Larry David and Curb to break eight hundred more rules than network TV would have ever allowed him to get away with. Sometimes the show seems like a mean-spirited Seinfeld, other times paying homage to madcap comedies of yesteryear. But the show has always been riotously funny.