Currently the options for calculating a score for a piece of SCORM content is either using either the latest attempt or average of all attempts.
The problem: Users passively reviewing content may create a new attempt at a quiz and lower their overall score. Once a user has successfully passed a quiz, it would be undesirable to lower their score based on a new attempt.
The solution: Add an option to accept the "highest" score. This is a commonly used scoring mechanism available on most LMS offerings specifically to prevent learners from being penalized for reviewing content.