The 22-year-old scored twice as the Gunners defeated 10-man Leeds United in the English Premier League on Sunday at Emirates stadium.
Nketiah has now scored four goals in 18 league games for Arsenal so far this season.
"He is doing what he has done all season," Arteta told Sky Sports after the win over Leeds.
"When he’s on the bench, when he’s sitting at home or when he’s on the pitch, this boy doesn’t change, that’s what we absolutely adore him, and he deserves what is happening to him.
"He has the right environment. The right personnel around him and now he is going to get judged for what he does when he is on the pitch and before he didn’t have that context."
It was a fourth successive win for Mikel Arteta's side.
The victory strengthens Arsenal's 4th position on the league table with three matches left to play and now holds a four-point lead over Tottenham in fifth.