The cart summary text is set in
To change this text extend the layout with a custom module or theme and change the summary block text argument
<argument translate="true" ...
The rule is working correctly as per the configuration.
If ALL of these conditions are TRUE :
If an item is FOUND in the cart with ALL of these conditions true:
Manufacturer is Adidas
This rule says if there is any item in the cart with the manufacturer as Adidas, then apply 10% discount to the whole cart and not just to the specific product....