I don't know how old you are but for me, 11 years at one club is a long periodWell you're long of making his point. None of those players stayed at Leverkusen long. That's the only, if you stay long enough you get infected and never recover. Tah is now so infected no team wants him
Moreover, I think this is an unfair comparison. Dortmund sends all their good players to Bayern so of course they'll be winning titles after leaving!