It is officially holiday shopping season, and though some of us want to invest in covering an entire wall in our house with an interactive video screen, we aren’t quite to that point just yet.

Marketplace Tech host Ben Johnson isn’t thrilled about that, and he says to blame technology and cost.

Building digital video screens is not easy. Our screens use a layer of glass over these tiny transistors that convert code into images. And to make big versions of these screens is entirely too difficult.

“If you get one little tiny transistor wrong, after you’ve manufactured this you actually have to throw the whole thing out,” says Johnson.

Manufacturers that want to make these screens have to build vacuum chambers into the factory, but that costs a pretty penny.

“It costs like $100 million just to make the factory that makes these things,” says Johnson.