In simple terms, it is a third-party application (often used alongside Crew Chief or standalone mods) that shuffles the deck. It strips away your control over the mundane and forces you to become a driver again.
The biggest killer of racing game longevity is "decision paralysis." You sit down to play, spend 15 minutes scrolling through 180+ cars trying to find the "perfect" combo, get bored, and quit. project cars 2 randomizer
The Randomizer solves this by forcing you to adapt. It removes the comfort zone. You aren't practicing; you are surviving. It tests your race craft, not your setup knowledge. It teaches you to drive a heavy GT3 car on a wet Suzuka circuit, or a classic Lotus on a dirt rallycross track (if you really want to break the physics engine). In simple terms, it is a third-party application