Maybe that's true.

Maybe that's true, but when I look at an advertisement like this:

I immediately feel the urge to get to know this confectionery creation better.

This design embodies all the positive characteristics that a poster meant for display on a billboard should have:

We don't need much time to see and remember all of this.
And driving through the streets, we'll encounter it several times.

The world would be beautiful if all outdoor advertisements looked like this Mentos ad.

Unfortunately, too often in my work, I see poorly designed posters.
Poor - meaning the advertisement is ineffective because the viewer has no chance to engage with it.
Of course, we must remember that a poorly designed outdoor project might turn out to be an excellent design for, say, print advertising.
But we're in the outdoor advertising business.

Nobody who doesn't stop and spend a few minutes will be able to tell who's advertising and what the ad is about, and of course, there's no question of building emotions and atmosphere in which we could make purchasing decisions.
A bad advertising design isn't just a loss for the client. It's also a loss for the outdoor advertising company. A bad design most often results in ineffective advertising.

Not only will the person who rented the billboards notice this, but paradoxically, everyone will notice it. They'll notice - because they won't pay any attention to this advertisement at all. Colorful images will flash before their eyes, very often these images will repeat, but few people will figure out whose advertisement it is and what it's showing.

We often hear then: outdoor advertising doesn't work. That's true, this kind of outdoor doesn't.
But, ladies and gentlemen, properly utilized outdoor advertising works brilliantly.
Like in the Mentos advertisement.