The Eighty Five Percent Rule for optimal learning Nature. That is, the optimal error rate for learning is 15.87%, and the optimal accuracy is around 85%. We call this the Eighty Five Percent Rule for optimal.

The Eighty Five Percent Rule for optimal learning Nature
The Eighty Five Percent Rule for optimal learning Nature from twopintplc.com

The 85% rule means it's OK to make mistakes 15% of the time for optimal learning. There's space to improve without being too easy. "Perfection is not going to be optimal for.