About Rounding Adjustment

I don’t understand why for some prices and taxes if I apply a discount of 10% the result of the Rounding Adjustment is -0,01
Use Case: I have a item with price 35 EUR and I create a Sales Invoice with only this item, apply Sales Taxes rate 21 and Additional Discount over Grand Total of 10% and the result is Rounding Adjustment is -0,01. My currency is EUR
I see this link Invoice rounding issue
But i don’t needed this Rounding Adjustment

Disable Rounded Total !!!