Seeing as you're having problems understanding very basic English I'll make it easier for you.
You said he was better based on potential and ceiling, newsflash - Ndombele was better than 95% of Premier League midfielders before we signed him based on potential and ceiling, what does that tell you?
If that's confusing you I'll use another City graduate to make it easier for you to digest, Sancho - he was one of the best up and coming young players in the world when he left City, what happened to him?
Following the examples above do all players go onto fulfill their potential? No. Is it a guarantee that every player hits their ceiling in their career? No. Did you 100% know Palmer would be this good this early in his career? No you didn't. If you did then you should be managing fucking Man City instead of sitting in your arse in your underpants making up stories on the internet.
Now based on the above do you understand what I'm saying? I didn't even say you were wrong, you said he's better than Johnson based on potential - I questioned your opinion when you said he's better than Johnson, I asked you based on what?
Hindsight merchant.