One mistake is bad. Two mistakes even worse. Two mistakes in the Champions League final to condemn your side to defeat? Unacceptable.
Being a goalkeeper is a lonely position at the best of times but there are probably no words that can accurately begin to describe just what will be going through Loris Karius' mind as he trudged off the pitch in Kiev. No amount of sympathy from his teammates would have been able to console the 24-year-old after he endured the worst night of his career.
The young German made two of the worst mistakes any professional goalkeeper has ever made in a major final, costing his side dearly as Liverpool suffered a 3-1 defeat to Real Madrid on Saturday, seeing a potential sixth European title wither away into nothing right before their eyes. There's no way of sugar-coating it. His performance in the Champions League was positively lamentable.
There is no defending Karius' blunders on the pitch and he will be the first to understand that his mistakes do not belong anywhere near a Champions League final. However, no matter what happened, the world needs to remember that Karius is a human being and his mistakes, whilst catastrophic, were simply that. Mistakes.
To Karius' immense credit, the German stopper was seen to approach the Liverpool faithful apologetically following the final whistle in an act that took an admirable amount of courage.
Speaking after the match, Karius said: "I don’t feel anything right now. Today I lost my team the game and I feel sorry for everyone.
"I’m sorry for everyone – from the team, from the whole club – that the mistakes cost dearly. If I could go back in time, I would. I feel sorry for my team. I know I let them down today."
Goalkeeping is arguably more mentally demanding than any other position in football. The pressures exerted on a goalkeeper are magnified, every action scrutinised. The pressures of goalkeeping at the highest level have taken their toll before now, with former German international Robert Enke tragically taking his own life in 2010 and ex-Premier League goalkeeper Chris Kirkland openly discussing his battles with depression and anxiety whilst he was playing.
There is now a genuine worry that Karius' performance may lead him down a dark path and its up to Liverpool to ensure that this doesn't happen.
With regards to his future at the club, there is no doubting that Liverpool do need to invest in a new goalkeeper. Karius' place in the starting lineup needs to be re-evaluated but his place in the Liverpool setup does not.
It seems as though Liverpool's current deputy, Simon Mignolet will be on his way out of Anfield this summer and its unlikely that Klopp will want to ship out both of his current keepers. There may be doubts lingering over Karius place as a first choice keeper, but his young age will act in his favour as he still has plenty of time to rectify his previous mistakes.
But sentiment and sympathy can only go so far and Liverpool do need to bring in someone who can provide more consistent performances. Now is the time to go for broke and make strides to bring a truly world class keeper. They have been continuously linked to keepers such as Roma's Alisson and Atletico's Jan Oblak and, if they are to improve their side, they will have to ignore the extortionate price tags and go for broke.
So where does Karius go from here?
He will have a long summer ahead of him as he will not be a part of the German World Cup side this year, leaving him to reflect on that torrid night in Kiev. However, if assurances are made regarding his future at Anfield then that may put some of his worries at ease.
It may take some time for Karius to even consider donning a pair of gloves, but when the time comes, he needs to ensure that he has a tight support network that can give him every bit of encouragement and motivation he needs.
There will be a delicate balance between building the German's confidence and pushing him to improve the areas of his game that require urgent attention.
There are some games which you simply cannot come back from. Think back to Robert Green's nightmare in the 2010 World Cup, or more recently Joe Hart's shortcomings against Iceland in 2016. Here's hoping that this is not the end for Loris Karius and is instead simply a temporary roadblock as he continues his career.