The guy is a Lazio level player. At Lazio there are no expectations. You can play great for 2 games and then disappear for 3 games. At Inter you need to perform on a constant base.
It isn’t about how good you possibly can perform once in a while, it’s about the consistency in your performances on top level. That , and you must be mentally fit to perform at the highest level.
Correa (or Arnautovic for that instance) has neither.