Suppose I found a superb project over the game, but I do not require it now (maybe doesn't necessarily fit my current role, or I currently have a better role). Usually, I will try and "sell" it - publicly list it and wish to replace it with another player to acquire a certain currency. The idea is the fact, during any real free market, this project might have no value in my opinion - but it really does preserve value for other people, therefore we can make us both better by swapping (assuming she has provided me with some value) Something) in turn).
In principle, I can try and replace it together with the different devices I need (as opposed to some POE Currency items). But such as the real world, this barter transaction has numerous shortcomings that contain almost never been used.

As with many role-playing games, so as to trade, both players need to be in the same game area. This seemingly insignificant requirement actually produced natural friction over the transaction. Usually, when I am within the game, I play games perfectly - while a potential buyer sends me a message nevertheless he is enthusiastic about what I am selling, I have to halt what I am doing then meet A buyer area (among the towns or players "hidden"). If both players are accustomed to  POE Currency Buy trading within the POE, this process normally takes less than a minute, however, it is a little annoying and partially breaks the overall game flow.

So ever before I decided to quit selling equipment at a price below a clear price (1 "chaos ball"), believing that the smaller profit is just not worth the time I spend - I would rather continue playing the overall game itself. If the device doesn't sell at the least 1 "chaos" eventually, I just do away with it to release my "store" storage.
Basically, I have determined the exchange should have a net profit of a minimum of 1 "chaos" or otherwise not at all - it is my "exchange price" (with respect to the difference between players, certainly).
In an expression, this effect can result in compared to the transaction costs in real-world stock markets - the exchange itself runs on the small area of each transaction is a brokerage fee, creating friction.