I notice the very tip of my tongue goes numb or won’t move into the correct position to pronounce a word at the end of the day. We get tired, our brains do also.
We are never going to be 100%.
I do shoot for the moon and take what I can get. It’s enough, but I never give up,
Listen to Andre Richelieu on you tube. Be proactive in giving yourself endorphins. Study endorphins also. It’s how I got to be this person after so much abuse and medical problems.