Immaturity is when you imagine that you are entitled! (children, but people can also regress; so normally, a child, as s/he receives, begins to imagine that they are entitled; but as they learn they can only get what their parents choose (for every normal parent both has and sets limits) they begin to adjust; but in truth, deep in their (namely, our) subconscious, is this desire – We all want, what we want, irrespective of, if it is good for us. (note, addictions etc.) for the very fact "I want!", ties the desire, to my desire to Fulfill My Desires (called ego) Hence a person who starts achieving, can easily regress (as well as narcissistic wounding, which creates a delusional sense of greatness; hence entitlement! hence anger! (for if someone doesn’t give you what you are entitled to, you get angry) Hence maliciousness toward everyone! but particularly as also a jealousy (for we all have innate jealousy) towards those who are happy (for an angry person cannot be happy)