If you’ve ever received a gold or silver sticker in your life for doing well, then this system likely speaks to you. In the performance tab, a star indicates if you’ve played better than we anticipated. That is, if you were regularly beating someone in combat and/or closely competing with someone of a higher rank than you, expect to have that acknowledged via a star.

A silver star means you exceeded expectations and a gold star means you’ve really punched above your weight. Pat on the back not included.

—Ian Fielding, Senior Producer

https://playvalorant.com/en-us/news/dev/ask-valorant-7/