You don't focus on the mistakes but you learn from it. If the mistakes are not studied, they'll be repeated. Chelsea is one team that has not learnt from the their previous mistakes. They went about buy every available player and they're doing the same again now.

All these teams have so much work to doe in order to reinforce their squads. They have to look for the lapses and positions that needs back ups. It's a very strategic process and it's something Manchester City has mastered well that's why they'll continue to dominate as long as Pep is still around. You can see now that they've added Savio to their team together with Doku, that would mean very good wingers that can dribble. Pep saw that his wings weren't that effective so he reinforced. That's what all teams should do instead of just buying a player because they player is good