soccer ball looks like, right?

It's as simple as black and white.

But that's not exactly what World Cup balls

have always looked like.

So what's the deal?

First things first.

You want a soccer ball to be as spherical as possible.

- In the old days we had balls that had the

bucky ball shape, the Epcot Center shape.

You had the 20 hexagons and the 12 pentagons.

And that was a very good approximation to a sphere.

But starting in 2006, in Germany, with the Teamgeist ball,

there were more creative ways to make

that approximation to a sphere.

- [Narrator] New technology enables Adidas

to start designing the balls with fewer panels,

which actually created a serious problem,

because fewer panels means less seams,

and, more importantly, a smoother surface.

- If the ball gets too smooth,

the air resistance for certain speeds goes up.

It's like kicking a beach ball.

- [Narrator] And that's exactly what happened

with the 2006 Teamgeist ball.

Players complained that the ball

didn't go where they expected it to.

So in 2010, Adidas compensated by adding

some texture to roughen up the surface.

Problem solved, right?

- Jabulani was a spectacular failure

because it was not rough enough.

When the ball would be kicked at certain speeds,

you'd notice it would look like it would slow down

dramatically in the middle of its flight.

- [Narrator] And the panels kept disappearing.

The 2014 ball had the fewest panels yet:

six!

But this time Adidas compensated.

- Despite having two fewer panels from Jabulani,

the total seam length around the ball

was actually 68% longer than it was for the Jabulani.

- [Narrator] So at least this time the ball

had the right amount of roughness

and flew further than the 2010 ball.

As for 2018?

- Total seam length on this ball,

it's actually 30% longer than the Brazuca.

So now you run the risk of the ball

being a little too rough.

- [Narrator] And again, Adidas compensated for this

by also making the seams shallower.

And studies show the Telstar 18

performs similarly to the Brazuca.

But it still has a bit more drag

and might not travel as far on high-speed kicks.

Regardless, all this begs the question:

If the goal is to produce a ball that's similar

to what athletes practice with for years,

why does the World Cup ball keep changing?

Turns out it's not about the players or the game at all.

I'm sure you can guess what it's all about.

- There's a new ball released for every World Cup.

But I think the primary reason is money.

- [Narrator] The 2018 World Cup ball

costs more than a hundred dollars.

- And these balls fly off the shelves.

- [Narrator] It's a pretty big investment,

considering you can get a simple replica for 20 bucks,

though they're not exactly the same.

- The technologies involved in these balls

are much, much greater than the balls we used as kids.

The panels on these balls are thermally bonded.

It helps keep the water out of the inside of the ball,

keep the water from making the ball

a little water-logged and heavier.

- [Narrator] But is it worth it?

We'll let you figure that one out.