The "number one goal" for PlayStation 4 is "to be the best machine", Sony Computer Entertainment America President Jack Tretton has said while speaking about the firm's plans for its next-generation console.

"We've never been first. We've never been cheapest," Tretton told Spike TV.

"It's about being the best. If you can build a better machine and it's going to come out a little bit later, that's better than rushing something to market that's going to run out of gas for the long term.

"In a perfect world you want the best machine that ships first that's cheapest. But the number one goal is to be the best machine and that's what we're always focused on."

Tretton is currently the only exec to discuss next-generation plans during this year's E3.

In an earlier interview, Microsoft chief Don Mattrick dodged a similar question when asked by Spike TV host Geoff Keighley.

But next-gen plans or not, Tretton still thinks there's plenty of life left in PlayStation 3.

"We've talked about the 10-year product life-cycle back to the original PlayStation and you have to climb that technology curve if you're a developer," he continued.

"This is the time when the value is the best and it's my favourite part of the console life-cycle. We tend to have very long peaks and this is when you can just focus on building great games and letting the consumer reap that investment that they made by having great gaming experiences."