Bayer Leverkusen's fate in the Bundesliga next season will be determined by their performance in upcoming matches, which I mean the pre-season matches, there are 4 matches:
1. Bochum - Leverkusen
2. Fortuna Sittard - Leverkusen
3. Leverkusen - Pisa
4. Chelsea - Bayer Leverkusen
Let's just see how Leverkusen performs in those four matches. If they can get good results, then we can expect Leverkusen to perform well in the Bundesliga next season.
The fact is that some teams hardly take preseason matches seriously, so using preseason to fully determine the performances of a team, I don't think, is ideal. It’s very possible for some teams not to do well during preseason, but during the main season, they will perform so well, even more than people expect. In fact, not all key players play in preseason, and one thing to note is that some teams' preseason matches are often against smaller teams. But let's see how Bayer Leverkusen's season will look, even though I don’t think doing well in preseason fully determines their overall season performance.