Before learning a skill, confirm that it has skill-level grading and that the grade can be turned into money

In plain words

The state is promoting the “new eight-grade worker” system (新八级工), which asks employers to link job pay to skill grade, and lets outstanding employees be certified at a grade without regard to years of service or seniority. This is a policy direction, and it varies a great deal between regions and employers. Only a skill that has a national occupational standard and a grade path can later lead to raises by grade, so check whether yours has one before you start.