Hey man, they're not a selling club alright!
You know what? I bite. Show me the posts declaring Borussia Dortmund as such, preferably without posts that are obvious wind ups, because if we start scraping the barrel that hard, I only need to look at the few gems that the European Super League thread has brought up to paint Manchester United as some of the worst scum of professional football.
So yes, Borussia Dortmund is a selling club or feeder club if you want to sound even more smug. The thing that I love the most about the usuage of this as an insult is that it really shows in what kind of bubble some United supporter live. Being a selling club is not a point of shame, it is the reality of more than 95% of the professional football clubs. Literally every club below the absolute elite is a selling club, because they will have to let go of their best players under certain circumstances as
a) they can´t match the wages and reputation of the clubs above them (thats the category Dortmund belongs to)
b) needs transfer income to balance the books and keep the club running (not the case for Dortmund)
c) uses transfer income to line the pockets of the owners (see b))
d) all of the above or a mixture of them
Professional football is one giant foodchain where the bigger fish eats the smaller one. Borussia Dortmund actually worked their way pretty far up that chain directly below the super elite. They sign the top players of smaller clubs all the time as they could be doing to PSV Eindhoven when they look at Malen as Sanchos replacement. This is just how this Sport works now.
In the same vain, I laugh every time when the accusation is leveled at Dortmund that they sign top level talents, develop them and then let go of them a couple years later as if this was somehow a dishonorable act. Yes, they do that, quite successfuly I might add. It is quite frankly one of the only ways they can compete with richer teams at least on short terms until they have to rebuild again. They can´t possibly target the Haalands, Sanchos and Bellinghams of the world once they have actually really taken off because they would be financially unobtainable by then. Have people no understanding how hard it is for clubs to actually inch towards the elite without the financial doping provided by investors, oligarchs or entire nations or the willingness to drown in debt? If you don´t go for potential, you simply settle for players with lower performance ceilings that are less likely to be poached away as they don´t really interest the elite. Then you challenge for nothing.