After every single game a day later or a couple of days later everyone is in the video room where the team performance is shown and dissected, individually players are shown (with the performance analysts as well) what they could/should have done; what they need to work on and how to do with the coaches/one on one coach (if thought necessary) - what you often can't do is take all that work on the training ground onto the pitch with you - especially if it's never been previously addressed, for example, you can see players do it day in day out on the TP, but then make exactly the same mistakes in a game and show the same lack of composure or self-believe when it matters - in a competitive game.
Afraid Sissoko is a prime example - on the training ground he is awesome and even shows some great abilities to finish, with power too - but as we can see, put him in the 6-yard box and his decision making/self-belief/composure is somewhere in the middle of English Channel!
Incrementally, Sissoko has vastly improved and that's because he was worked on again and again and again - sooner or later, he will finish and then just watch his confidence soar and even at this late stage of his career, he'll never look back.
I could go on and on about players weaknesses and how they're addressed through training routines and one on one coaching, but at the end of the day as hard as you try to get into their heads to make them use their footballing intelligence or bring to the fore the composure you try to embed into their game - they have to do it.
I think Sissoko is overthinking it when he gets in the 18-yard box now and suspect it's too late to fix - but we will see, I expect to see him to kick on this season and if he remains injury-free to have his best professional career season - ever!