There are several alternative synonyms one can use to replace the phrase "was no good." Some of these include ineffective, inadequate, useless, impractical, unsatisfactory, and subpar. Each of these synonyms carries its own subtle connotations and can be used in specific situations. For example, "ineffective" might be a better replacement for describing something that did not work as intended, while "unsatisfactory" can be used to indicate something that did not meet expectations. By using a variety of synonyms for "was no good," one can add depth and nuance to their writing and speech.