Dortmund and Bayern Munich they have new manager so we can't judge early about their performance later because Bundesliga even hasn't starting yet but i am sure the management of both teams will be targetting similar achievement that whether it Dortmund or Bayern Munich will be attempts to broke the domination of Leverkusen who performing fantastic last season with Xabi Alonso
Dortmund with Nuri Sahin and Bayern Munich with Vincent Kompany and both are young managers which this is their first time experience to train big teams especially Vincent Kompany with Bayer Munich because i am sure people will be watching Bayern Munich under Vincent Kompany and they will start criticizing hard to him if Bayern Munich failed to performing well next season
Actually Nuri Sahin will not experience much pressure at Dortmund compared to Vincent Kompany because when the management has decide to hire him as the next manager to replace Terzic position Dortmund management hasn't targetting the trophy next season but they want Nuri Sahin can bringing Dortmund to compete for top 4 again and i am confident he can able to do that but for top 4 position Dortmund has strong opponents such as Stuttgart and Leipzig
While we can't "judge" the managers, we can judge the teams and say that if Dortmund somehow finishes above Bayern, then it means Kompany sucks, and Nuri is great. I mean last season they fired Tuchel because he couldn't get them the title, this season they won't look at Kompany twice if he starts to be terrible.
It's obvious that he is not really well experienced, he hasn't managed any good clubs, and this would be his first test, and if he gets like a few bad results after like 10-15 games, there is a potential that he could be fired very quickly. Normally Bayern doesn't like firing managers during the season itself, they wait until the end, but it's different for Kompany, he is a nobody in the managerial world and that means he might turn out to be a very wrong decision.
This is why I believe that it's possible for him to be fired easier than anyone else. Not that they have any other coach in mind, but I am guessing that someone at the top of the free agency list would have been better easily. They spent so much to break him away from his contract too, makes no sense to pick him, definitely not a smart idea at all. Should be something questionable, we will see when the season starts.