Ireland full-back Rob Kearney says Leinster's poor season was down to their culture diminishing in Matt O'Connor's last year.
Leinster finished outside the top four for the first time in ten seasons and lost in the Champions Cup semi-final, which prompted O'Connor and Leinster to part ways.
Speaking at the launch of Canterbury's Irish rugby jersey in Galway, Kearney also questioned the leadership shown by the younger players when their seasoned internationals were absent, but welcomed the appointment of Leo Cullen as interim head coach.
"Last year we probably moved away from some aspects of our culture, it seemed to diminish a bit," said Kearney.
"Leo's huge strength is that he's a Leinster man through and through. He understands what it took during those tough years to get us from a team of nearlies to be a really good achieving team in Europe.
"I just think we (experienced players) were in and out a little bit. We had a few injuries. I think Matt spoke a little bit about it as well.
"Having players coming in and out of the environment with younger guys maybe not stepping up and taking on the leadership and onus on them as much as they should have. Small little things like that that can be improved on next year."
Cullen and Leinster will have to plan without their World Cup squad members for the first seven weeks of the season and once again those youngsters will be asked to bear the most of the playing burden.
The Six Nations will bring similar problems for the Leinster squad, but Kearney says all of their focus will have to be on the early weeks of the season and coping without their big names once again.
"There will be a very front end of seven weeks where they'll have a huge amount of works to do themselves.
"I think the guys back there in camp realise how important those first seven weeks are going to be to determining the rest of our season."