Cut his teeth elsewhere
With this potentially being Arteta’s first managerial post in football, the Gunners would not want a newbie taking over the reigns after a man of over 20 years in charge is to leave. It’s like going from one extreme to another.
Everton could be the perfect job for Arteta to cut his teeth, relatively low expectations compared to Arsenal and a better network of help should things go wrong. Arsenal can not afford to gamble on their next manager.