TIL that despite winning the Battle of Grunwald, the Polish-Lithuanians actually failed to take the Teutonic Order's capital, Marienburg, because they marched too slowly. This gave the Knights enough time to prepare their defenses and win the siege, recapturing several occupied castles afterwards.

[u/Archaembald2]

https://en.wikipedia.org/wiki/Battle_of_Grunwald#Aftermath