Excellent points, I completely agree with everything you commented and I would still like to add other characteristics that I consider important for a professional player:

Study the odds - See what the profit margin is in games, how many have already won with certain bets, check out sports betting tips, see if there are strategies that can help you bet more accurately, and so on.

Have emotional control - Good players, on a difficult betting day, manage to maintain control without despair. Because the first thing is to bet without thinking to try to recover what you lost, this can certainly lead to a disastrous result. Being calm and knowing how to manage emotions is a mandatory requirement for a professional player.

Specialize in certain areas of betting - Do not play in any and all sports, modality or market. On the contrary: focus on a few and study everything you need to about them.

Develop a method and follow predetermined steps - Having your own method is essential, as this is what will define your most successful strategies. Including, having a betting method makes it easier to identify where you are going wrong, and what you need to improve. No more “crazy” betting without a clear strategy.