The term 'second guessers' refers to individuals who often doubt their own decisions or the decisions made by others. Some synonyms for this phrase include doubters, hesitators, waverers, and vacillators. These are individuals who are uncertain or indecisive about their choices, and tend to overthink or analyze situations before acting. Other synonyms for 'second guessers' include fence-sitters, equivocators, and ditherers. In addition, they may be referred to as armchair critics, Monday-morning quarterbacks, or backseat drivers, as they tend to criticize or question decisions made by others after the fact. Overall, these terms all describe individuals who struggle with decision-making and may benefit from gaining more confidence in their choices.