Timed exclusives on the Epic Games Store are the result of “some combination of marketing commitments, development funding, or revenue guarantees,” Epic Games founder Tim Sweeney recently explained on Reddit.

The digital storefront launched in early December and currently offers a curated selection of PC and Mac titles, along with an 88% cut of revenues for game developers. It aims to be “very pro-competitive,” Sweeney said in response to a Reddit user who claimed that timed exclusives like Supergiant Games’ roguelike dungeon crawler “Hades” were “anti-consumer.”

“When lots of stores compete, the result is a combination of better prices for you, better deals for developers, and more investment in new content and innovation,” he said. “These exclusives don’t come to stores for free; they’re a result of some combination of marketing commitments, development funding, or revenue guarantees. This all helps developers.”

The downside to all of this competition is the proliferation of game launchers, Sweeney said, but it’s a problem that could potentially be solved via decentralized software. “There are ongoing conversations about this,” he said. “But multiple stores are necessary for the health of an ecosystem. When there’s only one, their natural tendency is to siphon off more and more of the revenue, which then go to monopoly profits rather than creators.”

Epic is also working on a review system for its new game store, Sweeney revealed in a tweet on Wednesday. It will be based on the existing system in the Unreal Engine marketplace and it will be opt-in by developers. “We think this is best because review bombing and other gaming-the-system is a real problem,” he said.