Musar do Koheleta 12:1

The ninth [reason] is that during the days of his old age - with the absence of the power of emotion - he does not have the reserve of strength to create new paths in his heart, to arrange thoughts with which to fight his impulse, to attain virtues and to toil and strive in Torah and in [his] actions (and in the worlds). As it is written (Ecclesiastes 12:1), "So remember your Creator in the days of your youth, before those days of sorrow come and those years arrive of which you will say, 'I have no pleasure in them.'" Therefore, it is appropriate for a person to rush to save his soul, like the matter that is stated (Psalms 119:60), "I have rushed and not delayed to keep Your commandments."