Any decent game is going to have several elements to it, here's my thoughts.
Luck.
Builds can be made to minimise the randomness of the dice involved but luck will always be a factor, when attacking or defending if you roll all one's (or blanks) then you're in trouble!
Skill.
A good list commanded poorly will still lose, adversely a weak list controlled brilliantly can exceed it's “on paper” expectations.
List.
The other side of the luck coin. List synergy and prowess is a major factor, a well built list can negate some events of pilot skill.
Take a look at the old game of snakes and ladders, this is entirely luck. Any player could win regardless of their grasp of the game as each and every action is random, decided by the roll of the dice. Then Compare this to chess, an entirely different game. Both players have exactly the same forces and there is no element of luck whatsoever, the game is won or lost completely with yours and your opponents skill.
Many tabletop top games combine the above attributes and then go on to add list building. Imagine playing a game of chess using only the eight pawns whilst your opponent used only the eight back row pieces, that would be a very one sided game.
