Defeats are never easy to accept.
Sometimes you have to admit the better team won. Other times you realise that good fortune was simply not on your side.
But on other occasions, you feel like Fiorentina did in Munich.
The Viola went to Germany as massive underdogs and came within a whisker of getting away with a 1-1 draw which would have put them in the driving seat for Champions League quarterfinal qualification.
A horrendous error cost them that result.
With the game all square and the Italian team down to 10 men—more of which later—it looked like the Tuscan defence might hold.
A shot was fired in, Sebastien Frey parried it and from the rebound Ivica Olic headed it forward to Miroslav Klose standing a couple of yards offside.
He nodded the ball home but the Fiorentina players looked around for the flag of the referee's assistant to be raised.
It never happened.
Of course, a football official does not have an easy job and often has to make decisions in a split second. They deserve a bit of slack most of the time for any mistakes they make.
But not this one.
It was obvious at normal speed, it was obvious in slow motion and it was obvious in the 300 replays after the match. The officials got it badly, badly wrong.
We'll never know how the game might have panned out without that decision.
Bayern might easily have got a goal anyway through another source or in another manner.
However, that will not ease Fiorentina's fury.
They had played an impeccable game up to that point. With all the players following Cesare Prandelli's instructions to the letter they smothered out Franck Ribery to great effect.
Arjen Robben caused more problems but for the first half the Viola seemed to have matters under control.
The Allianz Arena appeared subdued and about 5,000 Fiorentina fans started to sense a famous result might be on the cards.
That hope took a blow just before halftime.
A clumsy challenge sent a Munich man flying and although Mario Gomez slotted the ball home afterwards, the referee brought play back to give the penalty.
The impressive Robben calmly gave the home side the lead.
It should have been a platform for Louis Van Gaal's side to get more goals but instead it was the visitors who hit back.
A lucky bounce off Stevan Jovetic from a corner fell invitingly at the feet of Per Kroldrup.
The big Dane swivelled and scored.
It gave the Viola a vital injection of confidence at a key moment and they stood toe to toe with the Germans and looked as likely to score as their hosts.
But then came Massimo Gobbi's red card.
It was a foolish obstruction, definitely, and maybe he did deserve to go for an early bath but his sending off did not seem consistent with other decisions.
Mark Van Bommel had gone in two footed on Riccardo Montolivo earlier in the game and escaped with a yellow.
And Klose was also only booked for a potential ankle-breaking lunge on a Viola defender afterwards.
In context, then, Gobbi's expulsion from the game seemed a little harsh.
It also ruined a delicately poised match.
For the final 15 minutes plus injury time, Fiorentina could think only of defending.
Yet they held on resolutely until that missed offside decision which will take some time for the Serie A side to digest.
Of course, a 2-1 defeat away from home is still a positive result and it gives them every chance of turning the tie around back in the Artemio Franchi.
And their display gave them plenty of encouragement too.
But a grave error has had a fundamental impact on this last 16 fixture.
Bayern Munich will now kick off in Florence knowing that a goalless draw will be enough to see them through.
They should not have had that luxury.