I've watched Die Hard 17 times.

I never get tired of it. Ever.

I'm there for every "What, do you think I'm stupid Hans?", every "Come out to the coast, we'll have a few laughs", and of course, every "Yippie-kai-yay motherfucker." I know every beat, every cut, every line, and I look forward to every single of them. Especially (Spoiler Alert!) that moment when Hans Gruber takes the express elevator down from the 87th floor of the Nakatomi Plaza.

The point is I know how Die Hard ends. The suspense is gone. So why do I still watch it if the central premise of every great story is suspense? Well, because suspense may be why we watch.

But it's not why we rewatch.

We never talk about the rewatchability of ads, which is odd because advertising is literally based on rewatchability. No media plan on the planet has ever suggested that the target only see an ad once. Even Super Bowl ads, ads that are made specifically for that one game in February, are uploaded online weeks in advance of Super Bowl Sunday.

Back in the day, people were deemed to have been 'effectively reached', or effectively persuaded, by an ad if they were exposed to it something like 14 times in a 30 day period. I can only imagine that number is even higher today as you can quite often see an ad 14 times in one night.

So, if that's the case, the question to agencies should be less "will they remember the brand after the first time they see it" and more "will they hate the brand after the fourteenth time they see it?"

And I don't use the word hate lightly.

I watched an NFL game the other day, and I saw the same Montana's Roadhouse ad 11 times in three hours. (For real. I counted.) The ad is not good on the first viewing (any ad that begins with "Hey Canada!" never is) but it's excruciating after the tenth.

By the fourth quarter, I loathed Montana's, and made a promise to never go there because I don't want them to ever think that bludgeoning me with their ad is a marketing best practice. It's like the Montana's team watched that famous clip from the Family Guy, and thought "Hey, you know what? Stewie's onto something there."

Maybe the reason we never talk about rewatchability is because it has very little to do with 'the message.'

The reasons we love an ad the first time is the message. ("Mac is easier to use than PC" or "Snickers satisfies my hunger") It's relevant, or surprising, or meaningful. But the reason we love it over and over are the details - the little things that have very little to do with the message and everything to do with the repeated enjoyment of it.

Like in this recent ad for Roku.

The first time I saw it, I was wondering why the family were all yelling at each other. It's then revealed that it's because they can never find the remote and they're all really frustrated. Nice insight. My wife and I have this 'discussion' at least twice every week. They then show that Roku's "find the remote" feature allows you to easily locate it (and presumeably, save on trips to your marriage counsellor.)

The message was clear, and the benefit was obvious. Check and check.

But now that I know what's going on and how it ends, what's in it for me the second, third and 20th time I watch it? In this case, lots. I've watched the spot at least 20 times and here are the things I look forward to each time.

1. The little girl's double foot stomp on the stairs. (That kid steals the show.)
2. Mom's hair and makeup. She looks like she hasn't slept in a week.
3. The opening shot of Dad's butt. You don't see that every day.
4. Dad and son screaming "I LOVE YOU!" to each other.
5. That they found the remote in the cupboard where the coffee cups are.

And that doesn't even count the last shot of the ad where the family is now happily watching TV. Over Dad's left shoulder is the little girl (who, as she tells us in the spot, "isn't allowed to watch TV because she's only 5!") quietly peeking over the couch. It's a great touch I only noticed on the 12th view.

That's rewatchability!

The main benefit being that I happily watch the Roku ad over and over rather than resent Montana's for yet again telling me about some stupid rib promotion. Or was it wings? I stopped listening the second time it came on.

I wasn't in the room when the Roku ad was presented, but I'd bet every dollar I have that none of my five favourite things in the ad were presented in that first meeting in the boardroom.

That's because the focus of the spot would have been (as it should have) on the idea: Frustrated family is looking for the remote and are yelling at each other all the time. Roku's "find the remote" feature solves the problem. No more yelling.

All the little rewatchable moments came after the fact, as the team worked on making the story funnier and funnier (and more and more rewatchable.) That they came after the first big presentation does not mean that they're not important.

It just means that the message is one thing, and rewatchability is another. And both are critical.

Because if repeated exposure to an ad is a given, repeated enjoyment must be too.