If a player makes on mistake he should not play again for some time, I don´t care if he played fantastic for 89min, because I´m only interested in the mistakes.
If a player have a bad game, he should be sold immediatly, because, as an expert on this things, I know that a players career is over when he played a bad game.
The standards of the players must be on the highest level. Messi played a bad game against Chelsea last year, and even missed a penalty, so he is not good enough.
SAF also needs to canche his assistents. I will recomend someone like me. Since I never been involded in the game on any level, I haven´t picked up any of the negative ideas that players are humans and such. My expertice is to tell you after game what you should have done, I think that will come in very handy.
If you don´t understand this simple rules, you are old and stubbern, and should be replaced.