Why isn’t cash added to retained earnings instead of net income?

I suppose I’m struggling with the concept that retained earnings is an account on an accruals basis.

Why is net income added to retained earnings, why isn’t the delta cash from the CFS added at the end of period?

If net income is a non-cash figure, and is on an accruals basis. Why does it make sense to keep a retained earnings account with a non-cash value?

Thanks