head to head
Neither is harder. They score identically on all four axes, so the difference between them is in kind, not degree.

Execution · Competitive PvP
Definitive competitive tactical FPS balancing aim mastery with team strategy.

Execution · Competitive PvP
The Source-engine era of Counter-Strike's aim-and-economy tactical formula.
Counter-Strike: Global Offensive leans Execution (Competitive PvP); Counter-Strike: Source leans Execution (Competitive PvP).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Counter-Strike: Global Offensive
Spray control and flick precision at the top
Counter-Strike: Source
Recoil control and crosshair placement decide duels
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Counter-Strike: Global Offensive
Anti-stratting and mid-round adaptation
Counter-Strike: Source
Outguessing rotations, fakes, and timing of human opponents
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Counter-Strike: Global Offensive
Information hidden until contact
Counter-Strike: Source
Hidden enemy positions until information is gathered
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Counter-Strike: Global Offensive
Utility lineups, economy, and default strats
Counter-Strike: Source
Economy rounds, utility lineups, and map control theory
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.