Here are some categories of emotional immaturity, see if you recognize yourself or someone else in these categories:
Egocentricism: Emotionally immature individuals are self centred and selfish. They have little regard for others and are preoccupied with their own ideas and feelings. They deeply believe that they are somehow special therefore demand constant attention, respect and sympathy. In counseling circles these individuals are known as "narcissistic personalities". Emotionally mature individuals understand that love is sharing and a mutual sense of security which allows vulnerability and strength.
Out of control emotions: Emotionally immature individuals express emotion through temper tantrums, prolonged pouts and rapidly changing moods. They get frustrated easily and over-react to perceived criticism. They are unwilling to forgive and are prone to jealousy pangs while their emotionally mature counterparts use their emotions as energy sources.
Dependent: Indecision is a sign of immaturity. Emotionally immature individuals are indecisive, impulsive, easily influenced and avoid responsibilities for their actions and deficiencies. They are sensitive to criticism, but insensitive to others' feelings and stay in unpleasant relationships to avoid change.
Gratification: children and childish adults often want everything now, and avoid enduring anything they do not like. They know little of personal responsibility and often rely on other people for care and protection. Their behaviour is superficial, thoughtless and impulsive. Their loyalty lasts only as long as a relationship seems useful and their management of finances is chaotic. If you are mature, you can delay your gratification and desires, and you can maintain your self control.