head to head
8 Ball Pool asks more than Grand Theft Auto V, and the gap is execution.

Execution · Practiced Mastery
Precise shot aiming plus planning the run-out several balls ahead.

Execution · Practiced Mastery
Sandbox crime playground spanning shooting, driving, and a persistent online economy.
8 Ball Pool leans Execution (Practiced Mastery); Grand Theft Auto V leans Execution (Practiced Mastery).
8 Ball Pool leans clearly harder on execution.
8 Ball Pool
A perfect aim-line cheat wins nearly every rack outright
Grand Theft Auto V
Driving and shooting demand decent inputs.
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
8 Ball Pool
Opponents alternate turns; little adaptive interaction to predict
Grand Theft Auto V
Online PvP exists but mostly gear/positioning, not modeling.
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
8 Ball Pool
Break spreads add some randomness to each rack
Grand Theft Auto V
Some mission and lobby randomness.
8 Ball Pool leans clearly harder on optimization.
8 Ball Pool
Position play and run-out planning separate good players
Grand Theft Auto V
Heists, money loops, builds learnable.
A matching score does not mean a matching test. Two games can both sit at 10 on execution and demand completely different things of you - which is why the reasoning above matters more than the number beside it.