head to head
Super Smash Bros. Melee asks more than WWE 2K15, and the gap is execution.

Execution · Competitive PvP
A platform fighter with one of the highest execution ceilings in any competitive game, layered on top of deep human reads.

Execution · Competitive PvP
Reversal timing and pacing against an opponent baiting your counters.
Super Smash Bros. Melee leans Execution (Competitive PvP); WWE 2K15 leans Execution (Competitive PvP).
Super Smash Bros. Melee leans clearly harder on execution.
Super Smash Bros. Melee
Wavedashing, L-cancels, and tech-chasing set an extreme physical ceiling
WWE 2K15
Reversal timing windows decide most exchanges
Super Smash Bros. Melee leans clearly harder on reads.
Super Smash Bros. Melee
Reading DI choices and opponent adaptive habits is constant and non-convergent
WWE 2K15
Human opponents bait reversals and vary move timing
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Super Smash Bros. Melee
Stage hazard RNG and spawn positions add marginal chaos
WWE 2K15
Chain-wrestling rock-paper-scissors minigames add randomness
Super Smash Bros. Melee leans clearly harder on optimization.
Super Smash Bros. Melee
Character matchup tiers and optimal movement routing are deeply studied
WWE 2K15
Move sets, stamina and match pacing are learnable systems
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.