Valve's Robin Walker has claimed that Team Fortress 2 allowed the company to carry out business experiments that will be vital to its future secuirty.
In an interview with Gamasutra, Walker, who was lead designer on Team Fortress 2, explained that the game's "secondary objective" was to explore new possibilities in both business and game design.
"[When the game shipped], MMOs were the dominant story in the industry, and one concern we had was that we might not be able to survive if we didn't build one," Walker said.
However, Valve lacked expertise in MMO design, and chose to incorporate specific elements into the game instead - "persistent item design and storage," for example. As the free-to-play business model started to dominate the MMO space, Valve used TF2 as a guinea pig again.
"We were starting to feel the same way about micro-transactions as we did initially about MMOs: that our company was at risk if we didn't have internal experience and hard data on them," he continued.
"In the end, TF2 has been ended up being one of the most useful tools we've ever built to reduce risk in our company's future.
"The thought that if we hadn't done it, we'd be here today without any data or experience with service based monetization strategies is quite terrifying."