There's always something new and exciting happening in the world of comic books. Well, that's what the myriad of publishers want you to think.Both Marvel and Detective Comics, otherwise known as the 'Big Two,' are publishing titans currently ruling over the comic book industry and for decades now have been battling back and forth for the biggest slice of what's left of the comic book market. Back in the 1960's, some comics were selling almost a million copies each issue, and nowadays a publisher is lucky if they're able to sell a hundred thousand copies of an issue. What happened? There are several different factors to consider, but there's no single right answer; people simply grew-up, comics gradually became more expensive, and more recently the condition known as 'event fatigue' swept fans worldwide.While sex may sell for movie and television audiences, it's death that sells in comics today, with several big-named superheroes who are constantly getting killed-off and brought back to life for the sake of sales and not story.The last time comics were as popular as they once were was only a mere 20 years ago during the early 1990s. A few years prior, both Marvel and DC had crossover events that ran throughout all their titles, "Secret Wars" and "Crisis on Infinite Earths" respectively and it was a genuine success financially. With the epiphany that fans would shell-out cash for big events, both publishers went to work thinking up new ways to up the ante, and keep the profits continuously flowing.DC killed-off Superman and that bought a lot of attention, both good and bad. Yes, "The Death of Superman" event sold like hotcakes, but story was being sacrificed for a boost in sales. While non-comic readers were buying all these issues to one day retire on, regular comic book fans were being ignored and forced to witness the destruction and death of some of their favorite characters. Green Lantern went crazy after being infected by an alien known as Parallax and ended up slaughtering the entire Green Lantern Corps after his beloved Coast City was destroyed.He later dies after sacrificing himself to reignite the sun. The Scarlet Spider, clone of Spider-Man, bit the dust after having an unfortunate run-in with the Green Goblin's glider. It didn't matter if a character was killed-off, because a year or two later and they would make a triumphant return, and make the publishers more money because it too was considered a collector's issue. Fans caught-on that dead didn't really mean 'dead', and a lot of people walked away from comics after the events in the 90's. And publishers have been trying to rein them back in ever since.This past decade alone has brought more deaths and reboots to the comics industry than ever before, because publishers seem to find it easier to kill-off characters and stage big events rather than tell entertaining stories. DC rebooted their entire universe last year with an event called the "New 52," where they re-launched all their classic characters with all new back stories and villains in 52 different comics, and it was a huge success. For several months they were actually leading Marvel in sales, until fans got bored and only focused on buying one or two of the 52 titles.Marvel recently attempted their own semi-reboot with the "Marvel NOW!" event, and, while not completely erasing decades of continuity like DC did, they just renumbered all their new series at no. 1 because apparently no. 1 issues sell. While Marvel actively denied copying DC's business strategy, the two publishers have been caught in a copycat-and-mouse battle since the beginning.Nowadays comics and comic book characters are a permanent staple in pop culture, ranging from video games to big screen movie adaptations. And yet the comic books themselves still have a hard time selling. Killing off major characters has become the norm in comics, because the publishers know it's a guaranteed payday for that financial quarter. But the fans have had enough, and they let their wallets do the talking as they expand their horizons and give the other publishers a shot.So next time you hear on the news a prominent character is going to kick the bucket, or there's going to be an event that changes the universe as we know it, the publishers are desperately trying to get you to come back into the fold. A year later that character will be alive and well again, and the publishers will be moving on to the next cosmic event.