A possible response to such an accusation could be:
a) I simply DON'T WANT to play this map.
b) I have a reserve hero; this map might be decent, but I'll wait for a better one.
c) The map is not very good, but I only have one reserve hero, so it's better not to risk it and end up in a bad situation.
d) I lost a lot.
e) Ufferton, Stracker, etc....
f) Ivor without edicts, Taz with 10 gnolls....
If you try hard enough, you can come up with more reasons.

Often, I choose option a) and it's extremely difficult to explain this logic.