The Gunners brought in the Brazilian on a free transfer in the summer after he failed to agree a contract extension with Chelsea.
Willian has failed to make a discernible impact at the Emirates and has registered just one shot on target in 12 Premier League games.
Despite his off-colour performances, the 32-year-old played the full 90 minutes as Arsenal slipped to yet another damaging defeat against Everton on Saturday.
The north Londoners have now lost seven of their last 10 league games and are languishing down in 15th place in the table.
Adams questioned the Gunners’ recruitment policy and insisted if their iconic former manager Wenger was still in charge, the signing of Willian would’ve never happened.
‘That’s lazy recruitment for me,’ the Gunners legend told Stadium Astro. ‘You’ve got to really question the recruitment process at Arsenal at the moment.
‘We’ve had some wonderful players and wonderful principles under Arsene Wenger, he went for a young player, you wouldn’t have even considered Willian if Arsene was still in control at the club.
‘For him a forward over the age of 30, physiologically he doesn’t think he can get that player to consistently to perform to the levels that Arsene would want him to get, it wouldn’t even have been on the agenda.
‘This is a straightforward agent recommendation, he’s got the same agent as the sports director [Edu] so it’s an easy option for him, three-year contract, there we go. I think it’s really poor recruitment.
‘And to have someone like Willian, one shot in 12 games. I’m like hold on put [Joe] Willock out there, we’ve got [Gabriel] Martinelli back in there. You’ve got other options.’