A level of proficiency is a degree of excellence in demonstrating a competency. Depending on the needs and expectations of the position, a person can be more or less able to master a competency.
Each competency in EVO.K.E includes the description of three levels of proficiency presented in ascending order (level 3 being the top level), with each level a progression from the previous level. Consequently, level 2 implies mastery of level 1, and level 3 implies mastery of levels 1 and 2. Using levels of proficiency helps you clarify your expectations of your employees, and explain what improvements are needed to meet expectations.
Note that the level descriptions, like the competency definitions, are only suggestions. Please feel free to adapt them to your corporate culture.