If I couldn't get the Atlas Points, the nexus should not be considered "cleansed"

There are many weird ways in which you can lose a Corrupted Nexus. Sometimes it's not even your fault. A misuse of the checkpoint and co-op systems after the first boss of the map is defeated can result in the nexus getting lost. It is also possible that you die before being able to pick up the stone.

But even if you just die too many times and fail the map. There is honestly no reason whatsoever for the game outright removing the Nexus. The player already lost a rare waystone of the tier they are currently in. The player also had many deaths and thus lost a bunch of experience. And now the player has to redo a whole mape with corruption and beat a boss and the corruption boss all over again. But currently the game will also remove the nexus from the map. This means that on top of all the punishment, you also have to go look for another nexus in the map. Sometimes the maps can be very huge with no nexii on sight.

I am being perfectly honest when I say that I personally know at least two people who were enjoying the game more or less but decided to quit it for losing a nexii like this. And like I said, it seems not to really have a good reasoning design-wise.