Left 4 Dead could've had player classes—but the game's co-lead put his foot down: 'no, that is the wrong way to go'

pcgamer.com:

Left 4 Dead has stood the test of time, more or less—and while there hasn't been a peep from the series in years, that's more down to Valve weirdness rather than a sign of a lack of interest from players. Half-Life was galactically successful, and we're all still waiting on a third game. Someday, Gabe, someday.

Part of Left 4 Dead's success was down to how straightforwardly good it was. You rock up, shoot zombies, and spam «pills here!» at every opportunity. There aren't classes or progression trees—and while a lot of those bells and whistles weren't common in the genre when it came out, it still made the game more accessible and focused. It's also why people are still playing it.

Classes are something Left 4 Dead ignores in favour of simplicity. According to the game's co-lead, however, things could've gone a very different way. In a recent interview with GameDeveloper, Chet Faliszek remarks: «I dearly love the team from Alien Swarm, but I don’t know how many times where I was told to make [Left 4 Dead] more like Alien Swarm.»

For those out of the loop, Alien Swarm is a top-down, class-based shooter Valve released for free back in 2010. It's a great time, but no-one really plays it anymore—due in part to how under-supported it was by Valve. You can still play it, it's just a 13 year old game that didn't really go anywhere. On the plus side, its code became the basis for a very cool Half-Life RTS mod, Lambda Swarm. So there's that.

«I kept saying, 'no, that is the wrong way to go. This game is more mainstream and accessible.' I didn’t want players to need a specific class or else they couldn’t, like, open a door or have a blocking ability.»

That's not to say that Left 4 Dead's formula can't work with a more class-based