Is the transition from life-death and re-incarnation in any way obstructive to a soul’s natural growth towards God? Don’t we lose track of our experiences and lessons learnt in our life if we keep getting born and dying over and over, especially ones on the spiritual path? This new search for truth in all our lives doesn’t count to changing wives, jobs and Guru? Excuse me if i’ve not understood it yet, but its an innocent question of forgetting what one was searching, which bothers!
I believe that you are asking if death and subsequent rebirth are obstructive to our spiritual growth — and more especially, do we, at the time of death or afterwards, forget or lose what we have learned or how we have grown spiritually?
Generally speaking, when we experience physical death, we only lose the physical body, but we do not lose our astral and causal bodies. In them are contained our egos (the soul’s identification with the body(ies) — physical, astral, and causal), our chakras and all past, unresolved karma. To learn more about this in greater detail, you might want to read: Karma and Reincarnation: The Wisdom of Paramhansa Yogananda, Volume 2, by Paramhansa Yogananda.
In our next incarnation, we may not remember the karma or the exact lessons we learned in the most recent past or any other lifetime, but the tendencies will be there within us anyway.
For example, if you have worked hard on yourself and tried diligently to grow spiritually through meditation and upgrading your attitudes, you'll probably be drawn into a family or situation in your next lifetime which will help you keep going, rather than hinder your progress.
Your soul, that unchanging part of you which is part of God, never forgets anything, because it is everything. Keep tuning in to that Greater Self through meditation and you have nothing to fear about "losing ground" spiritually just because of physical death or anything else.
"...all things are passing but God [and the God within you] never changes."