The English midfielder is enjoying his current loan spell with Newcastle United.
Willock has scored a few important goals for the Magpies this term, with the most recent being the winner in a 3-2 success over West Ham United on Saturday.
Asked about Willock's progress after his side's 1-1 draw with Fulham on Sunday, Arteta said: "I'm really happy with Joe because he scored a massive goal for their club.
"So when he produces big moments like that, for a young talent like him it's very satisfying.
"Joe can do it, he's got the ability and the desire and now he needs more consistency in terms of minutes and performances.
"That's great for his development and that's why we believed it [the loan to Newcastle] was the right option."