Why are we so bad at making good choices about our future? Why do we need to get everything now, immediately? Why can't we wait a while longer and enjoy better rewards later?
Given a choice of getting something little right now versus getting something considerably more later it always feels more tempting to get the instant reward. You need it right now. There is no guarantee you want it anymore after a while.
And besides, it's far in the future, surely there are more options coming up later to make things up.
Maybe so, but even then, your future reward would be even bigger. It always builds up on top of that which has already been gained. Or to be gained to be precise.
It doesn't matter if you are saving up or losing weight. You won't see the rewards until long time after you have started. And there is never a point to start too early.
Or having a moment of rest now and doing things later, all at once in a hurry. It's hard to think about it that way. It just feels you have all the time, so it doesn't matter to postpone things a bit and instead enjoy the moment. There wouldn't be time for it anyway after doing those things right away, right?