Hi Student.
You wrote:
“This is an issue of mystery and dissatisfaction.”
I have such similar questions myself, so I understand your curiosity.
Student wrote:
“why not the start.”
Here is a sutta that might be of use to those on the Path, whenever these questions arise:
“Malunkyaputta, if anyone were to say, ‘I won’t live the holy life under the Blessed One as long as he does not declare to me that “The cosmos is eternal,”… or that “After death a Tathagata neither exists nor does not exist,”‘ the man would die and those things would still remain undeclared by the Tathagata.
“It’s just as if a man were wounded with an arrow thickly smeared with poison. His friends & companions, kinsmen & relatives would provide him with a surgeon, and the man would say, ‘I won’t have this arrow removed until I know whether the man who wounded me was a noble warrior, a brahman, a merchant, or a worker.’ He would say, ‘I won’t have this arrow removed until I know the given name & clan name of the man who wounded me… until I know whether he was tall, medium, or short… until I know whether he was dark, ruddy-brown, or golden-colored… until I know his home village, town, or city… until I know whether the bow with which I was wounded was a long bow or a crossbow… until I know whether the bowstring with which I was wounded was fiber, bamboo threads, sinew, hemp, or bark… until I know whether the shaft with which I was wounded was wild or cultivated… until I know whether the feathers of the shaft with which I was wounded were those of a vulture, a stork, a hawk, a peacock, or another bird… until I know whether the shaft with which I was wounded was bound with the sinew of an ox, a water buffalo, a langur, or a monkey.’ He would say, ‘I won’t have this arrow removed until I know whether the shaft with which I was wounded was that of a common arrow, a curved arrow, a barbed, a calf-toothed, or an oleander arrow.’ The man would die and those things would still remain unknown to him.”
Existing in sansara is like being shot with that poisoned arrow. The antidote is Nibbana.
In my opinion, if the Buddha never explicitly spoke about such topics, I think it is of not much benefit to ponder at long lengths about them. Because the only being I’d trust to get the full/correct answers to these questions is from the Buddha himself, the best source. So if he answered any of these questions, it would most likely be in the Tipitaka, that is our second best source now without the Buddha. Otherwise we can only speculate/guess/theorize, and never find the true definitive/satisfying answer.