Buying young, promising, and cheap, to see how they do. You say you don't like it, fair enough, but in my opinion its a good policy, and we could turn up a gem, in fact Zinchenko might well be one, despite your opinion that he isn't. Kelechi is another example, OK he's moved on, but we took a risk, and made a decent profit on him, and if he turns out to be star in future we will probably gain further.
Nobody knows the first thing about this lad, but clearly he backs himself, and until I've seen otherwise he'll get my backing, and writing him off before he's even kicked a ball in training is pretty shoddy.
Oh, and I'm quite obviously not talking about buying the proven internationals that you mention, as I think all those were/are ready, and will/already have been successes.