All that goes up must come down

Remember the saying "All that goes up must come down". Similarly everything in this world has a beginning and end. For eg., take any great dynasty such as the Greeks, Egyptians, Romans, Persians. All the Dynasties began, reached its peak, and perished.
Another example in modern days is Europe and now the USA. Even more common example is the birth and death of a living organism. Even planets and stars have a beginning and end, for that matter the Universe/Multiverse (yes, I do believe in Multiverse for which there has been a possible explanation in String Theory) is no exception with the beginning attributed to the big bang.
This concept probably seems very obvious and trivial when pointed to but look closely and what we take as granted to be for ever seems virtually stupid. When ever we say for ever all we mean is that it would be for a long time to foresee but it is never for ever.
The only unknowns that pop-up are when, where and how is the beginning and when, where and how is the end. Therefore the substance of everything comes to how is the journey from beginning to end.