Because we come here to live this life, not to remember the struggles, triumphs or horrors of the past.
If we were to have easy recall of all our past-life experiences, we would become so distracted by all the scenarios, traumas, romances, losses, wars, tragedies, difficult relationships and personalities we have experienced and witnessed that we would be completely unable to focus on what this life, here and now, is supposed to be about. After all, we begin each new life as dependent little infants with a blank slate, focusing on learning how to walk and talk and interact with others in a specific family, society and culture.
Imagine yourself as a newborn infant with memories of every event from your previous lives. Or think about a sweet, small child of your own having perfect recall of every major trauma they have personally experienced or witnessed over a hundred lifetimes —
such as when they drowned in a sinking ship; got eaten alive by wild dogs; the time they went on a drunken rampage and slaughtered innocent people; the time they were a teenage girl gang-raped by foreign soldiers, or the time they once raped a boy in front of his parents; such as when they had to torture someone even though they knew he was innocent, or the time they were an elderly priest with an insatiable sexual appetite, or when they were imprisoned, abused, beaten, and starved to death in a POW camp …
The things is, it’s not the actual experiences that matter to us, but the lessons learned. After each life, the old personality is left behind as the soul absorbs any actual wisdom it can learn from its experiences. That wisdom is carried forward into future lives, not as explicit knowledge exactly, but more like a deep inner knowingness, or what we might call ‘instinct’ or ‘intuition’.
So while we don’t (usually) carry specific memories from life to life, we do carry our growing wisdom at a subconscious level, and use it intuitively. The more we manifest our intuitive knowing, the more we are being true to who we are given our soul’s level of evolution.