Looking at the most expensive ones most are failures.
top 20 transfers:
Neymar - failed
Mbappe - success
Joao Felix - not looking good
Griezmann- not looking good
Coutinho- failed
Dembele - failed
Pogba - 50/50
Hazard - not looking good
Cristiano - huge success
Bale - success
Higuain (from napoli to juve)- success
Maguire - jury still out
Lukaku - failed
VVD - Huge success
Luis Suarez - success
Nicolas Pepe - not looking good
Kepa - not looking good
Lucas Hernandez - not looking good
Zidane - success
James Rodrigues - failed
Out of the top 10 only three lived up to the expectations and out of the top 20 only 7 you can call without a doubt, gets some perspective on how risky is to spend big on players.