"SBMM" - aka skill-based matchmaking was a trending phrase on Twitter this week as the Call of Duty: Black Ops Cold War beta went live and players resorted to killing themselves over and over again in a bid to improve their experience with the game.
SBMM relates to the way matchmaking works in video games, and it has become a hot topic within the Call of Duty community in recent years. The idea is by deliberately gaining a negative kill / death ratio in matches, Black Ops Cold War's SBMM will essentially demote you down its skill ranking, and then matchmake you with players more your level (or you'll do better against).
The issue flared up with the release of the Call of Duty: Black Ops Cold War alpha, which saw players complain its SBMM was too harsh and lobbies were "like COD League Finals".