Realization, understanding? Usually those terms aren't associated with error.
Sure they are, just not in the moment you are certain of them.
"I had an understanding that you wanted the rent on the 30th of the month, but I realized February would not work and read the contract...so here it is on the 28th."
Logically, the understanding or the realization in this instance must, by force, be in error.
When I said there are innumerable examples, you can feel free to come up with a bunch on your own. Heck the mere existence of the commonly used phrase/sentence "I thought we had an understanding" blows your theory with only the sentence fragment and no detailed example at all.
Realization, understanding? Usually those terms aren't associated with error.