1) Something else is happening with that team.
For example thoughts of that manager to stay in League, maybe later change of plans.

2) I mean (when I read comments like - I was +10% better) that you must have at least +20% quality to consider yourself as a favorite.
Now maybe it's 30%.
For example if ATLETICO MADRID beat BARCA or REAL M. , it's not a troll result.

Now maybe we can say that even if Athletic Bilbao beat BARCA or REAL M. , it's not a troll result.
If Celta Vigo beat them, it's a troll.