What do American Idol, Dancing With the Stars, Survivor, Who Wants To Be a Millionaire, Hell’s Kitchen, Big Brother, So You Think You Can Dance, America’s Got Talent and Wipeout have in common? They are broadcast TV’s biggest reality franchises of the past decade. And they all launched in the summer. Summer used to be a time for the networks to try out innovative reality formats that had never been done on the Big 4 broadcast nets (ballroom dancing or singing competitions, shows about castaways on an island or strangers locked in a house) or had been gone from primetime for a long time (game shows). Now the broadcast networks are throwing on retreads of over-exposed formats from June through August, so it’s no surprise that nothing has stuck since Wipeout launched on ABC in June 2008. A slew of newcomers came and went over the past three months: ABC’s Expedition Impossible, Take the Money & Run, Karaoke Battle USA and 101 Ways To Leave a Game Show; CBS’ Same Name, NBC’s Love In the Wild and the similar It’s Worth What?; and Buried Treasure on Fox. The only new offering on broadcast to show a pulse this summer was ABC’s Extreme Makeover: Weight Loss Edition, helped by a solid lead-in and the fact that it is an offshoot of a popular franchise. Things looked as bleak on the scripted side, with ABC’s Combat Hospital, Fox’s sketch comedy In the Flow With Affion Crockett and NBC’s burnoff Love Bites barely registering.

That is in stark contrast to cable, which once again produced a slew of breakout hits: TNT’s Falling Skies and Franklin & Bash, USA’s Suits, ABC Family’s Switched at Birth, MTV’s Awkward and TV Land’s Happily Divorced, all already renewed for a second season; USA’s Necessary Roughness, whose pickup is pending; and Cinemax’s Strike Back, which also got off to a solid start. While not as many, there have been several standouts in the reality arena too, like rookies Nail Files on TV Guide Channel and Tia & Tamera on Style both posting ratings records for their networks. How can MTV’s Jersey Shore pack a 4.5 18-49 Live+same day demo rating in August when HUT levels are so low that most broadcasters don’t even bother to schedule originals? And the show does it in the 10 PM slot, where pundits say viewership is additionally depressed by DVR use.

That’s because, like all those broadcast reality series I listed at the top, it cuts through the clutter as being entertaining and original. When you see TNT dramas Rizzoli & Isles and The Closer rake in 10 million viewers in Live+7 in August, it makes you ask why the broadcast networks surrendered summer to cable, especially on the scripted side. Seinfeld‘s original run was in the summer. And Fox’s The O.C. too launched in the summer, the last scripted broadcast series to successfully do so. From then on, it’s been all cable, with such signature series as USA’s Burn Notice, TNT’s The Closer and AMC’s Mad Men all launching in the off-season. Meanwhile, broadcast nets’ only notable summer scripted originals have been Canadian imports, Flashpoint on CBS and Rookie Blue on ABC. And the CW has been sitting summer out altogether, something new president Mark Pedowitz is planning to change.