Until the greed of money is removed from this club, you should stop expecting anything good from this club.
Dortmund is in business to maintain the team's existence. Greed for money is necessary. We see them doing business to make a profit for the club. And they cannot retain players when the club's reputation and salary are not as high as big clubs. Selling when the price is high is a good choice for the club and the players.
I still hope big sponsors see the team's potential and are willing to invest in them. Dortmund will not be forced to sell their star.
The truth is that Borussia Dortmund would've been one of the most feared and strongest teams in Europe if the club's management didn't sell their best players over the last four or five years.
However, they've managed to remain as one of the best German clubs over the years and the only consistent team that's been giving Bayern Munich a good run for their money. If they had won their last German Bundesliga game last season, they would be the crowned champions of Germany last campaign.