First of all, their promotion may be related to personal reasons. For example, they have their own relationships and can get an approval from key people, so they are promoted faster. They are good at wandering in such relationships, using these resources, serving themselves or having such resources in their own families.
Second, their promotion may be related to their ability. Although some came in for a short time, they went to other departments, and some just came in to evaluate their titles. Probably related to one of their personal abilities, such as getting good grades in some public courses or performance classes.
Third, we should also examine the reasons why we have not been promoted. For example, I can't manage the relationship between colleagues and leaders without investing in some personal connections. Or lack of strength, insufficient attention to preparing lessons in class, insufficient efforts or insufficient teaching. These are measurable.
Finally, if others get benefits, don't just complain, but take it as the driving force. Then I will study hard how to grasp such things, because many things are not decided according to a part-time job life.
Of course, in the workplace or some jobs, you will face some unsatisfactory situations. At this time, you should learn to adjust your mentality. Don't blindly create contradictions and conflicts, but also seek the opinions of others. I can also make progress from it.