When it comes to describing individuals who are successful, we generally associate them with terms like accomplished, prosperous, thriving or victorious. However, the antonyms of an "unsuccessful person" could include words like accomplished, prosperous or thriving with a prefix of "Un" such as unaccomplished, unprosperous, and unthriving. Other antonyms include terms such as lucky, fortunate, or blessed. Furthermore, using negative antonyms like failure, loser or nonstarter borders the line of negativity and could potentially harm someone's self-confidence. Ultimately, the choice of antonyms controlling how you describe unsuccessful persons can significantly affect how a person thinks and feels about themselves.