"For these players I think European football is a really massive part of their development," said O'Neill.
"The Everton players, because of this excellent [Uefa] cup run, have improved, and we would like to draw some comparison to that. That's why I would like to qualify for Europe, because I know from my own experience at Celtic the improvement of the players when they got used to playing European football.
"These lads [at Villa] are young players and they are developing very quickly and European football would help their game enormously.
"Young players get a chance to shine in the side and the club is definitely progressing. European football would help cement that. If it doesn't happen, it doesn't happen. But we haven't given up on that by any stretch of the imagination."