OttoLearn recognizes that learners will forget things over time. To account for this, the system will automatically calculate a small decrease in mastery strength over time in Concepts that the learner hasn't engaged with.Each learner's rate of forgetting on a Concept is based on how proficiently they executed that Concept's associated Activities.For example, if a learner has a mastery strength of 3 on a Concept and stops performing any of that Concept’s Activities, they will drop down to a mastery strength of 1 over the course of around 60-70 days.OttoLearn will project into the future to predict when a learner may drop below their target mastery strength due to forgetting. This information is used to determine which Concepts to present Activities from in each Training Session and Training Moment.ProTip: Learning progress is not affected by forgetting and will only drop if new content is added or a learner answers an Activity incorrectly with high confidence.