You reap what you sow.
Meaning in life depends on what individuals do. Specifically, the consequences resulted from one’s actions over time.
So when pondering on the meaning of life, good to examine one’s actions. Because:
Sow a thought, reap an action; Sow an action, reap a habit; Sow a habit, reap a character; Sow a character, reap a destiny. ~ Samuel Smiles
What do you want out of life? And what’s in your thought?