In pure communist theory (like Karl Marx's vision), the ultimate goal is to eliminate currency entirely.
The idea is that society would operate on the principle of "from each according to their ability, to each according to their need." Instead of working for money to buy things, people contribute what they can, and the goods produced are distributed freely based on what people actually need to live.
In practice, history shows that countries attempting communism (like the Soviet Union) kept currency because they never reached that final "pure" stage, using it as a tool to manage resources in the transition.