Jan 5, 2011 23:01 GMT  ·  By

Valve, one of the biggest independent game developers out there, has just defended, through its marketing director, Doug Lombardi, the surprising and frankly 'schizophrenic' release schedule that it currently employs.

Valve is one of the most popular game developers out there, largely because it releases quality titles, which are extremely fun.

Sadly though, the titles are usually delayed so that the company can iron out all of the problems, meaning you can never know when Valve actually launches something.

The company is also quite surprising with its development plans, as after it launched Half Life 2, it promised that the next installments in the series would be episodic ones, released once every 18 months or so.

That didn't happen, as Valve took its time to release products like The Orange Box, which included Half Life 2 Episode 2, Portal and Team Fortress 2, but also launched a new franchise, in the form of Left 4 Dead, which immediately received a sequel, one year later.

Lombardi explained the erratic release schedule, saying that Valve carefully plans its new games, in order to keep things fresh.

"I think it's fair to say that Valve never approaches a product release the same way twice," Valve's Lombardi told Issue 100 of Xbox World 360 magazine (via CVG).

"With Half-Life 2 we took six years to create an epic sequel, then we immediately shifted to episodic releases, which were then followed by the release of a new IP (Left 4 Dead) which was given a sequel in less than a year. "

"Now, with Portal 2, we've taken a couple of years to produce a full sequel to a game that was launched in episodic size. The point is not that we're schizophrenic, but that we try to [plan] every game in a way that's best for [it], given market conditions and other factors."

Valve is now hard at work on Portal 2, which will be launched for the PC and Mac, as well as for the PlayStation 3 and Xbox 360 consoles, on April 18, in North America, and April 22, in Europe.