1). Knowledge of character match ups and/or frame data. Knowing the ins and outs of the characters they are playing, as well as the opponents.
2). Meter management and planning. One of the most important things during game play.
3). A good player would play to the best of their ability without underestimating or overestimating the opponent, and learning from their mistakes overtime.
4). Knowing when and where to change your play style up (going from turtle to rush down to keep away and back again). Adaptation plays a pivotal role here as well.
5). Training on a daily basis and devoting time into leveling up and learning more about the game and/or character specific match ups.
6). The players ability to stay focused on the match in itself.
7). The players must keep their cool when they are forced on the defensive. They also need to know how to get out of bad situations and stay away from the corner. The players must understand how to control space during game play.
8). Knowing when to conduct frame traps, meaties, and mix ups on the opponent. Understanding how to bait, as well as punish the opponent for mistakes is a huge one for good players as well.
9). Knowing when to adjust or put a stop to your offensive rhythm when the opponent is planning on doing a reversal of some kind.
10). Being a good player also relies on reaction and timing, much like every other fighting game does. Always be sure to have an understanding of the games fundamentals, as well as character specific technology.