Two ways come to mind re: retirement. Luck/skill into a big payout via startups or tailor a series of jobs to get you a paid-off residence someplace you'd like to live. Carrying a mortgage into retirement is just too much of a financial restriction for most folks.

You need retirement savings that will cover expenses over any government pension you might get. I assume you're in the US, so there's little chance of a company pension... Basically, save as much as you can while living a reasonable lifestyle. And the killer question is whether or not you have kids - which, usually, suggests a partner having similar decisions. DINKS have more financial flexibility but less populated lives.

In a way, you should "burn the candle at both ends" while younger. Deferring everything until later puts you at risk to not having the physical or mental means to do what you'd like. Or, not having the people you'd like to do them with. I guess you could say "don't waste time". You only get so much and it grows valuable as you age.

And store up memories when you're young. You'll spend them when you're old.