Simple economic's question

Try to solve a simple quiz:

Imagine that you had a thing that you sold to a neighbor for 12 USD. But then you changed your mind and bought it, but for 13 USD. Then he persuaded you to sell it for 14 USD. But the story did not end there, and as a result, you again bought it from him for 15 USD.

And now the question arises: how much have you lost in these operations?

(the answer is under the picture)

Many will say that 3 USD, because I sold the first for 12, and bought in the end for 15. But this is the wrong answer! The correct solution involves adding two operations 13-12 and 15-14, and the result is 2. And the fact that the example refers to the same product does not matter.

And now remember how often in life some historical knowledge of price changes actually prevents us from making the right choice? Sometimes it is very difficult to understand where logic ends and memory begins. In particular, it is done by the beginning investors or traders who finally lose the money on the stock exchanges.