He came on as a fresh pair of legs, like what others have said we are in a relegation fight, the player that he replaced was doing more than him before he came off.
Kean should be going out of his way to impress as he is 19 years of age at a new club, seen the shift other players had put in and worked really hard for 20 mins or so, but no he was jogging around.
What it also shows to other players is if you don’t put 100% effort in you won’t get in the team, this lad seems to have a Lookman type of attitude