One of the harder parts of Blavatsky’s explanation of karma and reincarnation is that she insisted that only the best in people goes on to form part of the divine Ego. That is: a person without a shred of goodness in them will be lost to the higher self. They will have lost the opportunity for learning experiences for the Higher Self and it is in that sense a lost life.
Yet – the higher self that was attached to that criminal person goes on to form a new personality in a new life… (From Blavatsky on Karma in 1883)
let us suppose that A lives to that age when a person becomes an adult and begins to bloom fully into life. No man, however vicious his natural tendency, becomes so at once. He has had therefore time to evolve a Karma, however faint and insignificant. Let us further imagine that at the age of eighteen or twenty A begins to give way to vice and thus gradually loses the remotest connection with his higher principle.
At thirty or say forty, he dies. Now, the personality of A between fifteen and twenty is as little the personality of A from twenty to thirty, as though it were quite another man. Even the physiologists divide the physical personality into stages of seven, and show man changing atoms to the last, every seven years. The same with the inner man. The fifth principle of the sensual, highly depraved man, may well and will perish, while the Karma of his youth, though not strong and complete enough to secure for him a bliss in Devachan and union with his higher principle—is yet sufficiently outlined to allow the monad a grasp on it for the next rebirth. On the other hand we are taught that it so happens sometimes that the Karma of a personality is not fully worked out in the birth that follows. Life is made up of accidents, and the personality that becomes, may be hindered by circumstances from receiving the full due its Karma is entitled to, whether for good or for bad. But the Law of Retribution will never allow itself to be cheated by blind chance. There is then a provision to be made, and the accounts that could not be settled in one birth will be squared in the succeeding one.
In other words: though the thoughts, emotions and actions of person A will add up to negative results in total – in each specific life there may well be strokes of luck in which person A (our criminal) gets the chance to change his life for the better. After all – for most people this is easier when life is good than when things are tough.
The law of harmony also means that each ego gets a chance to improve itself. If not in this life, then in the next. All lives are part of the One Life. Only those who insist on working against nature and consistently work for themselves only will ultimately loose the chance to better themselves. But most people are somewhere in between. Good one moment, bad the next. Selfish perhaps in financial things, caring in other ways. Or vice versa.
Ultimately, so Blavatsky tells us, what is taken on into our next life isn’t all of what we were in this life. What we take on is merely the fragrance of what we learned. The essence of the essence as it were. And what our personality remembers of that wisdom is dependent on the lessons that need to be learned in the new life. Negative karma can prevent us from remembering when a bigger lesson still needs to be learned.