What's Ты never know how much Ты cherished something until its gone mean?

It just means Ты didn't know what Ты had until Ты didn't have it any more, Ты didnt' see it while Ты had it, but once Ты didn't have it any еще Ты realized what Ты missed... So I guess it also means appreciate what Ты have now cuz it could be gone tomorrow. :]

Ты have to keep 2 things in mind:
1. We want what we can't/don't have.
2. We get easily bored and want the Далее best thing.

When Ты say that Ты don't know how much Ты cherished something until it's gone, Ты mean that when Ты own it Ты do not fully appreciate just how great it is until Ты no longer have it.

It might или might not mean that they cherish something more. It all depends on the context of the situation and just how fickle that person is.