João Felix is a Portuguese forward who recently transferred from Benfica to Atletico Madrid for a transfer fee of 113 million Euros (Wikipedia). According to TransferMarkt, his market value has exploded exponentially from under 1 million Euros just 2 years ago (TansferMarkt). He is a rising superstar talent, currently at just 20 years of age. His exploding value and transfer fee show the economic impact of potential. His transfer fee was nearly twice his market value, and the premium likely comes from the fact that he is just 20 years old and already considered a world class player.
As a result, he really could only end up at the well funded clubs like Atletico Madrid. Over the last year, however, TransferMarkt has lowered his market value. This is likely pushing his market value back towards his true value based on productivity. The honeymoon effect of the young star is expiring.
Felix began his youth career at Porto before moving to Benfica at age 15. He stayed at Benfica through age 19 when he transferred to Atletico Madrid (Wikipedia). The big winner is this transfer is Benfica. Because of the previously mentioned economic and political factors, Benfica, who invested in Felix through their youth academy, made far more money than Felix was producing for the club.