Our organization has a use case for a grading scheme not based on percentages. The justification for this comes from the need to get away from the traditional 100% scale. The traditional grading scheme is uneven with passing grades constituting only 40% of the grading scale (60-100%), but failing grades making up 60% of the grading scale (0-59%).
The use of a non-percentage grading scheme allows for a different point spread. An example is shown below of what is possible.
5 - Excellent
4 - Good
3 - Average
2 - Fair
1 - Poor
0 - Incomplete
While this is a simplistic example, it illustrates the idea that the values for "passing" constitute an equal amount of the grading scale, if not more than that depending upon the organization and their "passing" criteria.