The Gunners were among 14 clubs to vote in favour of moving the Premier League's transfer deadline forward to the Thursday before the start of the season.
"I believe people will adapt by making their decisions early," Wenger was quoted as saying in the match programme ahead of the visit of West Brom to the Emirates.
"What happens now is that you're contacted 48 hours before the end of the transfer window and someone say, 'Are you still interested in this player?'
"You worked on that deal for three months, they closed the door and then suddenly they open it up again with two days to go. It's all rushed decisions and very hectic in the last week.
"Once you go into the games as well, you don't know if the players are speaking to their agents on the afternoon of the game or to other clubs, so they don't focus on the game. It's not right how it was."