What does paradise lost is sometimes heaven found mean?

I would have to say that it means that despite losing something, somtimes you gain something as well. I'm guessing it's an allusion to Milton's Christian Epic: Paradise Lost, which inadvertantly glorifies Satan as a byronic hero who tries to stick to God by making Adam and Eve sin. We, as Christians believe us being descendents from Adam and Eve, have lost Paradise but have now gained freedom of choice and a sense of earning when/if we go to heaven. Though, in context it wouldn't have to mean exactly that... it could just mean that sometimes not getting what you want makes you a better and happier person.

If we can say that "paradise" is a dumbed-down version of the glorious "heaven", then it means that by losing the lesser thing (paradise), a greater thing may be gained (heaven)