Studying material once and being tested three times leads to lower confidence and mastery compared to multiple exposures.

“the students that study the material once and then are tested three times on that material they think that ultimately they're going to perform least well for instance they ask them their confidence how well do you think he would perform on a test of this material in two weeks or in a year or in six months or even tomorrow they report that is the students in the study test test test group report much lower confidence in the material much lower sense of Mastery of the material compared to the students that were exposed to the material four times”

“when you're exposed to material over and over and over again you think you've learned the material in fact your confidence that you've learned the material increases with each subsequent exposure to the material but actually you haven't learned it at all compared to the people that are exposed to the material and then take tests on the material”