One of the worst investments Chelsea ever made was signing Lukaku for nothing in the club. $113M is just too ridiculous to buy a player that was above 27 years old and then only to be loaned out for $8M for the same club that sold him, Inter was smart to make money with him and Chelsea was desperate for another Champions League trophy in the bag and yet, the man never participated in the journey, I think Chelsea is bad in making good financial decisions and this thing has been for long right before Toed Boehly bought the club, it will better if the review some of their staffs before they become broke like Barcelona that can not sign big players again due to FFA; Caicedo and Enzo always ring on my head whenever I think about their midfield.
I wouldn't say Chelsea was stupid or Inter was smart because Lukaku was worth for such big amount at that time, Chelsea was making mistake, but this kind problem has to way to know if Lukaku will not able to play in Chelsea as good as he used in Inter.
While signing both Caicedo and Enzo are obviously clear mistakes since Chelsea willing to spend money double from their market value just because they have a lot money.