When the consumer is unclear about a certain product, chances are, that product won't do well.
And that's why Sony believes PlayStation TV didn't sell. According to a Game Informer interview with Sony president of worldwide studios Shuhei Yoshida, the problem centered on the company's inability to explain the concept:
"It didn't capture the consumers' imagination. It's a hard concept to explain. You could say it's a mini-console, it's a video streaming device. If we say it's a mini-console, like other mini-consoles, people expect a better device like PS4 or Xbox One. It's short in that delivery.
When you say it's a video streaming device, there are other devices with higher def video. It has some unique things like remote play of PS4 games. It can do many things, but it's not easy to say this one thing is extremely good. I think that's the reason we were not able to convince people at the original price."
At launch, PlayStation TV sold for $100 in the US but it has since been heavily discounted in most stores. Now, you can find it for as cheap as $40 or $50. The idea of being able to stream Vita games to your TV isn't a bad one, certainly, but it couldn't have helped that the Vita just doesn't have that many games. Perhaps that's the underlying issue here.