Atalanta didn't win with luck rather it was proposed changed in game setting and thrashed Bayer Leverkusen in the Europa League final, therefore handling Leverkusen their first defeat of the season which was in total dismay for Bayer Leverkusen and their supporters. We could remember vividly how the club won the Bundesliga title without a record of defeats but did attain to draw points.
Why could something like that happen to Bayer Leverkusen in the Europa League final match, because Atalanta, who had also beaten a new team from England, also looked at their opponents quite carefully, especially since Bayer Leverkusen at that time was quite viral because they had never lost to any opponent. So this makes Atalanta's own spirit and pattern of play improve and become better because Atalanta can also get a sense of pride when they succeed in beating Leverkusen in the final match, which is an important match for both teams.
Although it is difficult to avoid defeat, unfortunately, their defeat occurred in the Europa League final and was also their only defeat in that season. Obviously, even though they can still force themselves to accept the results, I think it is very clear that deep disappointment must have been felt and/or experienced by them. Because of course, it would be difficult for them to repeat the same great achievements during that season, being undefeated and having a big chance of getting the treble winner, but they failed. Although it would be good to build experience, still, great moments like that will be very difficult to repeat.