The phrase "cons of joining" implies a negative aspect or downside to becoming a member of a particular group, organization, or club. There are many different words and phrases that can be used as synonyms for "cons of joining," depending on the context and tone of the situation. Some commonly used synonyms for "cons of joining" include disadvantages, drawbacks, pitfalls, downsides, hurdles, challenges, barriers, obstacles, and impediments. Each of these words emphasizes a slightly different aspect of the negative consequences that may occur when someone decides to join a particular group or organization, highlighting the potential risks or barriers that may need to be overcome in order to succeed.