Nothing on the macro level, because you can waste today and get on with whatever you were doing, tomorrow.
But there is more to it than meets the eye.
The memory of what you do today will be stored in your body and the body will remember it until eternity. This remembrance is what we call karma. That’s on a higher plane and on a philosophical level.
On a more practical level, if what you do today and is not aligned with what you are after then you are going backward, and instead of the one, you are taking two steps back. One step back because if you waste today, you’ll waste a day that you could have used to move forward towards your goal. Another step back because by wasting time you reinforce inaction and this makes moving forward much more difficult the next day.
And, by wasting a particular day you become more prone (than you were a day earlier) to living a wasteful life.
We cannot be scared of this situation and think that we are fighting a lost battle. Because as human beings it is almost impossible to live a perfect life and not waste a single day.
There will be all kinds of days in our life, and there will be days we end up wasting. We can just be mindful of what is on stake and utilize our days towards our purpose when we can. If we do this often and kept the wasted day count low, we’ll be fine.