How Kakashi's mental health negatively effected his strength and why he was getting stronger and stronger throughout the story.
Have you ever wondered why Tsunade was surprised that Itachi defeated Kakashi and was so angry that she scolded him for losing?
That's because Tsunade personally knowing Kakashi's power level as a Shinobi and that he shouldn't have lost that fight ... Then what happened?!.
Aside from the things I explained in the second half of this post, Kakashi was actually rusty, after Hiruzen got him out of Anbu and before he gets team 7, Kakashi's mental health was at it's lowest, he lost the Anbu missions which despite not being good for him and was actually making his depression worse, it's was the only thing that was keeping him busy, so now he had too much free time, he was failing all of the students he got and apparently he wasn't being sent to S or A ranked missions and according to his own statements he stopped training too
And here in his fight with Zabuza he states that it has been so long since he had a fight like this
And here he once again confirms that he hasn't had a fight like this since he left Anbu
Now, remember when Kakashi was teaching team 7 to walk on trees and was explaining chakra control? Kakashi explained that the physical AND mental energies combine to form chakra.
And this is why having a bad mental health can effect the Shinobi's overall strength greatly.
Then Kakashi gets team 7 and slowly things starts to get better gradually especially in Shippuden when he tells Naruto this
And then he got to meet his father and forgive him and know that because of it his father too can now move on and can finally join his mother.
And then during the war he got the chance to properly say goodbye to Rin, Obito and Minato and then later they even get Sasuke back.
He finally gets to move on.. even the Sharingan that was a constant reminder of his pain and failures was gone. When he says "As of today Kakashi of The Sharingan is no more" it holds a much more deeper meaning than just losing the Sharingan. "Kakashi of the Sharingan" was the man who had the weight of the whole world on his shoulders, who was always burdened by his guilt, his failures and everything he lost, that sad broken man who used to be called "Kakashi of the Sharingan" is no more. The new Kakashi gets to have a new beginning with all of the friends and precious people he still has, who has filled the hole in his heart, in a new era of peace, the peace that they all fought so hard to get and now they finally have. And this is why Hokage Kakashi is much much more stronger than he ever was. The current Kakashi has a perfect mental energy combined with a perfect physical energy (especially after losing the chakra drain of the Sharingan and the great toll it used to put on his body) and he is even training and learning so many new powerful Jutsu and inventing new ones like it's stated in Kakashi Retsuden. The new Kakashi finally gets to use his full potentials without all the emotional baggage that used to hold him back 🥺❤️
