A good example is this; World of Tanks takes Luck, because if you're matched against a tank 2-3 tiers above yours, you won't be able to do shit-all to them in regards to damage, because you can't penetrate their armour, or because all your shots bounce; 99% of tier 4 and 5 tanks get set up against Tier 7+ tanks for 'scouting' which turns into horrible, horrible rape.
Mechwarrior online takes skill because regardless of what 'mech you're in, all the weapons will do the same damage. A medium laser will do 5 points to you if you're in a Jenner or if you're in an Atlas (and, coincidentally, both 'mechs have the same ~number~ of medium lasers), but the Jenner pilot has to rely on its speed and jumpjets to avoid getting hammered by a bigger 'mech's heavy guns that the recon-type can't really carry.
A skilled light 'mech pilot can kill an unskilled Assault pilot. A skilled WoT tanker in a tier 4 can only do scratch damage to anything tier 6 or higher.