This is will be too bad for dortmund if it is true, dortmund has always have the nature of selling their best players. They don't care to know if they need this players , them selling their best players is affecting their performance to win trophies.
If that's what they consider, it means that Dortmund doesn't really aim for trophies every season so they are still considering selling their best players to other teams when there are very tempting offers. The point is that Dortmund are only concerned with money for themselves without thinking about the careers of their players. Obviously this is very unfortunate because Dortmund should have kept the best players to win trophies, not just wanting to earn money from selling the best players.