The life is meant to experience great thing exceedingly while maintaining what you've acquired so far and never loose it, you'll certainly value something you loss than just having it the first time.
A nice observation. But I think this feeling of valuing something more after losing it often depends on the person’s situation( how easily that item or assets can be replaced) . For someone who doesn’t have the means or opportunity to easily replace what was lost, the pain of that loss is more deeper and that is when he begins to value what he lost.
However in the case where the person is rich and capable enough to get back and replace that lost item or asset without much effort, then he is more likely to have a lowered sense of value.For example, someone losses his phone but as a result of his wealth, he is capable enough to buy a dozen more of that phone or even more. In this case now he ay not feel the regret as someone who spent all his life savings just to get a single of that phone.