Any poker player that claims they never make a mistake is a liar. Even elite professionals do, on occasion, make an error in their decision-making. Mistakes are part and parcel of the game because No-Limit Hold'em is a game played with incomplete information, plus poker players are only human.
The WPT Global Blog has published several poker strategy articles of late as it attempts to help its vast customer base improve their skills. A recent article details common mistakes made by players; how many of them are you guilty of?
Overestimating Your Ability and Playing For Stakes That Are Too High
Many poker players believe they are much better at this game than they actually are.