The six driver stats are all 1–20, but each one drives different mechanics. INT shapes mistake severity and L&C efficiency; PAC drives raw lap pace; CON drives mistake probability; ADA shapes recovery and pressure resistance; STA paces fatigue; AGG drives overtake attempts.
This page will give a stat-by-stat breakdown with examples — “what does +1 PAC actually buy me?” — and the priority order for evaluating offers.
For the short version, see the Glossary entries for INT / PAC / CON / ADA / STA / AGG.