At this point will re-post the snippet list from my second post that tersely lists what one psychiatrist thought were examples of how emotionally immature persons might act. This time with numeration one can just refer to instead of restating whole sentences.
1. Someone allows a friend to move in for a few days, and the friend won’t leave. The host is miserable, their life is disrupted, and it costs them money, but ridiculous justifications prevent them from setting a healthy boundary and forcing the person to leave.
2. A person is verbally and emotionally abused by their grown sibling and continues to go back for more, because “it’s family.”
3. A woman in a relationship with a man who cheats on and abuses her, and she claims she’s helpless to do anything about it.
4. People in jobs or careers and have families but enjoy a partying social life that disrupts their health and relationships.
5. Anyone who whines and complains without taking action to change it.
6. Emotionally reactive in the extreme. Yelling, snapping, a temper tantrum, name-calling, shaming, pouting, refusing to speak.
7. People who seek revenge and/or say, “I don’t get mad, I get even.
8. Any adult says, “He/She/They won’t let me.”
9. Blamers and who won’t take responsibility for their actions.
10. People who don’t take care of themselves.
11. Talkers, not doers.
12. Grown son, sits at home playing video games with a package of jellied donuts by his side, while his parents work long hours.
13. Afraid to be alone.
14. Will not work even though the family needs the money.
A question for each is, to hypothetically provide examples of how any might be categorized with motivations as emotionally immature? To start, I'll give a couple examples below and could do so to each of the above though some might not always be due to emotional immaturity.
For example #9 above, is a clear example of OP item 4 reacting defensively without adequately as an adult bothering to reasonably consider what other parties may be offering, even if done so calmly, constructively. Often done so immediately, as though any personal criticism by others is an attack they immaturely react to without consideration. And that usually comes with emotion because of OP item 6 also tending to be overly emotional, easily angered an immature reaction even when they ought not be. And once they are so angered, it is usually futile trying to reason with such persons until they later calm down if ever.
At work places, managers, tend to be very perceptive to ways their new employees might react with emotional immaturity during annual reviews that also reflects item 1. A wise person upon hearing such criticism ought first explain how they understand what is related has merit and then with adequate relative terms add other factors in play.
For example #7 above, may be those, often in working environments, that also tend to hold long grudges even for seemingly petty reasons that even though one may have since whatever, seemed to have developed a friendly cooperative team relations with, when they see clear ways to hurt the other person, often indirectly with innuendo behind their back, work to hurt the other person that has obviously been quietly emotionally grating and gnawing at them in the background as they otherwise mask their real feelings directly they cannot let go, due to item 6 emotional immaturity. May sometimes involve "company politics" that is a bit different with emotional motivations when those involved are vying for higher power and pay positions.
That also can play out in male/female relationships where one party after months of what had been apparent peaceful relations that one had thought were resolved on both sides with meaningful conversation, suddenly upon some new emotional situation, drags out much old supposedly resolved emotional laundry again, an example of emotional immaturity most adults learn to leave alone once resolved earlier.