Today it happened again that I wanted to post an answer to a question, which all of you know can take some time to write, but some minutes ago the question had been deleted by the owner.

For the (currently) few who can see the deleted question which IMO is on topic regardless of the OP stating:

I have the following code, I know it's inefficient because sporadically it throws an OutOfMemoryException due to the ToArray() call".

I had been tempted to hit the "undelete" button but hadn't been sure when to undelete a question.

When should one undelete a question which was deleted by the owner of that question?

Today it happened again that I wanted to post an answer to a question, which all of you know can take some time to write, but some minutes ago the question had been deleted by the owner.

For the (currently) few who can see the deleted question which IMO is on topic regardless of the OP stating:

I have the following code, I know it's inefficient because sporadically it throws an OutOfMemoryException due to the ToArray() call".

I had been tempted to hit the "undelete" button but hadn't been sure when to undelete a question.

When should one undelete a question which was deleted by the owner of that question?