the user's past gameplay history, comparing it to all other users, as to suggest new games that may be of interest to them. As these experiments mature through end-user testing, they have then been brought into the storefront as direct features. The September 2019 Discovery update, which Valve claimed would improve the visibility of niche and lesser-known games, was met with criticism from some indie game developers, who recorded a significant drop in exposure of their games, including new wishlist additions and appearances in the "More Like This" and "Discovery queue" sections of the store. Steam Charts were introduced in September 2022 and publicly track the storefront's best-selling and most-played games, including historically by week and month. Charts replaced a previous statistics page to be more comprehensive, and features content that had previously been part of third-party websites including SteamSpy, SteamDB, and SteamCharts. Games and account policies In June 2015, Valve created a formal process to allow purchasers to request full refunds on games they had purchased on Steam for any reason, with refunds guaranteed within the first two weeks as long as the player had not spent more than two hours in the game. Prior to June 2015, Valve had a no-refunds policy, but allowed them in certain circumstances, such as if third-party content had failed to work or improperly reports on certain features. For example, the Steam version of From Dust was originally stated to have a single, post-installation online DRM check with its publisher Ubisoft, but the released version of the game required a DRM check with Ubisoft's servers each time it was used. At the request of Ubisoft, Valve offered refunds to customers who bought the game while Ubisoft worked to release a patch that would remove the DRM check altogether. On The War Z release, players found that the game was still in an alpha-build state and lacked many of the features advertised on its Steam store page. Though the developers Hammerpoint Interactive altered the description after launch to reflect the current state of the game software, Valve removed the title from Steam and offered refunds to those who had bought it. Valve also removed Earth: Year 2066 from the Early Access program and offered refunds after discovering that the game's developers had reused assets from other games and used developer tools to erase negative complaints about the title. Valve stated it would continue to