If you apply in the morning, you sweat too much and the damage is done by the time what’s left of it starts working. But at night you have just the right amount of ‘baseline sweating’ to suck in the active ingredients and make a 'plug.’
Think about it- have you ever needed a deodorant refresher at night, and then you shower the next morning and feel the residue? It doesn’t seem to wash all the way off - but even if it did, it’s ALREADY IN THE DUCTS. You technically don’t have to reapply.
And it’s been on the label the whole time.
I just learned all of this. I don’t use this term often, but MIND. BLOWN.