There are various synonyms for the phrase "makes a bad investment." Some of the most commonly used synonyms include "investing unwisely," "throwing money away," "spending recklessly," and "putting money down the drain." These phrases describe the act of investing money without proper research, thought, or analysis, which can result in a significant loss of funds. Other synonyms include "making a poor decision," "gambling on a risky investment," and "investing in a losing proposition." It is crucial to carefully evaluate investment opportunities, gather information, and seek professional guidance to avoid making a bad investment.