waterfall why recalculate total

Hello everyone, I'm trying to define a power BI waterfall chart with an hot formula that helps to derive the calculation of the key steps of the waterfall across each product. The problem is that when it is not filtered any product the sum itself recalculate the step of the waterfall while I thought it would have just summed each variable calculated for the product and not reperforming the steps at the total level.

What am I missing in any option of this table or what is in the variable constructed the issue?

I'm attaching the power BI file with the example

https://drive.google.com/file/d/1nxgb9uatqGw_UP3xi-OxQtzS5LJfC7ZK/view?usp=drive_link

thanks for helping