If there is indirect exchange, it means that at least some people

in the society accept goods that they don't directly want (for

production or consumption). So there are media of exchange.

However, if money has not yet developed, it means that there is

no one medium of exchange that everyone is willing to accept.

In other words, some members of the community accept

Medium of Exchange #1, while some others accept Medium of

Exchange #2, and so forth. In a monetary economy, (virtually)

everyone accepts the same medium of exchange.