Wenger was thrilled with a high-octane run-in which allowed his side to reel in and eventually overtake Tottenham for fourth place.
He said: "Since February 1, we have taken more points than everybody else in the league, and I don't believe that's just down to coincidence, but just to the fact that the group has grown, this team has grown through the season.
"We lacked belief for long periods because we couldn't win a big game, but the Bayern [Munich] game changed our season away from home.
"In the last three months, I believe we have been remarkably consistent. We have won every away game, so it is a good springboard for next season, to transfer that belief into the start of next season.
"That means we need to have stability and strengthen our group if possible because there are many clubs out there with a lot of money, so the competition is very hard and there is not as much talent as money today in football."