We're not the first to say it but didn't summer TV demonstrate it?
Certainly, it did for ABC.
Casting killed not one but two of their summer shows.
Barry Sloane being given the lead role in THE WHISPERS guaranteed that all the strong work by Milo Ventimiglia and others would be ignored and that, week after week, the audience would dwindle.
Sloane had previously sent viewers fleeing from REVENGE so ABC should have known better.
But when does ABC ever know better?
MISTRESSES was a summer concoction which brought in an average of at least four million viewers for each of its first two seasons.
For whatever reason, ABC agreed to film the third season in Canada -- the United States of America's apparently not good enough for the American Broadcasting Company under Disney management -- and series star Alyssa Milano bowed out.
That should have immediately caused ABC to rethink the move.
Instead, it was full steam ahead.
And it only got worse.
Tiny Alyssa Milano was replaced with Jennifer Esposito who brings to mind the worst of Candice Bergen's film career. Esposito can't be a lead actress -- her entire career argues that -- from SPIN CITY all the way to BLUE BLOODS. She's also can't by tiny.
And dressing her in the sort of garb Bette Midler wore in STELLA -- and wore to look ridiculous -- just made Esposito more of an oddity.
The third season saw the show posting record lows for viewership.
If there's to be a fourth season of MISTRESSES, the only reason would be to rescue the show by bringing Alyssa Milano back.
Getting better ratings was ABC's THE ASTRONAUT WIVES CLUB but ABC's already taken the axe to that show announcing there will be no second season.
The casting there was the concept.
Sometimes the casting is a place (think Robert Altman's classic film NASHVILLE) or an idea or a concept. THE ASTRONAUT WIVES CLUB's casting was concept.
The same is true of CBS' latest summer hit, James Patterson's ZOO which posted excellent numbers early on but still held its own when the ratings declined. ZOO isn't about acting -- not even with James Wolk in the cast. Instead, the show's all about high concept.
That was true of UNDER THE DOME as well. And by season two, the audience was fleeing so CBS became desperate to plug the leaks with actual actors -- hence the arrivals of Marg Helgenberger and Eriq La Salle.
And that's the problem when casting is concept.
What works one summer seems tired the next.
EXTANT has held steady for CBS.
Maybe because the series stars Halle Berry? Maybe because the show attempts to move forward with each season and shake things up?
Maybe for both of those reasons and so much more?
Maybe because a real star like Halle Berry remains a rarity?
Watch Jimmy Fallon chat up one ridiculous person night after night throughout the week and grasp just how few stars there really are today.
Celebrities feed the tabloids, yes. They just don't draw in audiences for anything other than their tacky real life -- or 'real' life -- antics.
David Duchovny is a TV star. That's why AQUARIUS worked as an online entity and as an NBC broadcast entity (and why the show will have a second season). It's why Fox is doing a six-episode update of THE X-FILES.
Sometimes a show can have it all: strong casting, action, romance, you name it. The CW found itself with just such a show in BEAUTY & THE BEAST. In an inspired move, they chose to air season three in the summer.
And the result?
Ratings as strong as their fall 2014 and spring 2015 JANE THE VIRGIN -- ratings also stronger than BEAUTY & THE BEAST had in season two..
And, unlike on JANE THE VIRGIN, when Jay Ryan (Vincent) and Kristin Kreuk (Cat) exchange a look, it carries heat and meaning.
Fox had something similar in its limited run series WAYWARD PINES starring Matt Dillon, Juliette Lewis, Terrence Howard, Melissa Leo and Carla Gugino among others. The show proved that the mini-series format survives.
Other things were proved as well.
First of all, Netflix is now the premier network. In May, as broadcast networks were winding down their regular programming, Netflix began serving up original series: GRACE AND FRANKIE, SENSE8 and WET HOT AMERICAN SUMMER: FIRST DAY OF CAMP among others. It is now the benchmark for summer programming.
And though Hulu has failed to challenge that standing, in good news for the streaming service, they finally got their own original program worth watching in DIFFICULT PEOPLE.
It was a solid summer of programming in many ways.
But we will repeat the objection we made before the summer programming started: CBS, NBC, ABC, Fox and The CW all putting the bulk of their summer programming on Thursday nights was a mistake. Some of the ratings erosion returning shows faced could have been avoided if the networks had spaced their original programming throughout the week because, after casting, scheduling is everything.