I am using a liquid detergent and I use exactly the half of the detergent they say I should use. If a the washing machine requires 1 cup, I do half. Mostly because I don’t trust the company to put me over their interests.
Now, what will happen? Will my clothes end up staying dirty? Will it not remove stains which a full cup would have removed? Will surfexcel kidnap me and torture me for not obeying their commands? Help meeee!!
But they’re incentivised to tell you to use more detergent even if you don’t need to, leading you to needlessly spend more money.
You say that like that confirms their intentions or that detergent volume would ever be seen as a universal rule anyways. It’s so circumstantial it challenges the point.