That twitter quote is incomplete and completely out of context. He is talking about when he saw 18 years old Pogba first in training, he didn't know him and didn't expect anything special in first impression because he was a random youth player in Man U who didn't get a chance with senior team.
The continuation from the above twitter bit is is this:
"He was different from the others and I’m sad that [since re-joining United] he is not showing completely what he is. He has done fantastic in many matches but has not been lucky, with injuries and for other reasons. He has not been able to show, continuously, all his skill.”
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More critical of his 2nd tenure in Man U, but that's expected, everyone, Pogba included, has been dissapointed with the outcome and expected more from someone with such a clear x factor skillset.