You make an interesting point about something I thought I understood, but actually didn't.
I always assumed the point of this advertising approach was that it's messy, but it works. Someone who just bought shoes probably won't be buying a new pair ASAP, but there might be better odds than for any random person. Maybe they like shoes, maybe they'll return them, maybe that's their go-to gift for friends.
I genuinely hadn't thought it might just be an exercise in fudging correlation numbers to make ads look more successful than they are.
I always assumed the point of this advertising approach was that it's messy, but it works. Someone who just bought shoes probably won't be buying a new pair ASAP, but there might be better odds than for any random person. Maybe they like shoes, maybe they'll return them, maybe that's their go-to gift for friends.
I genuinely hadn't thought it might just be an exercise in fudging correlation numbers to make ads look more successful than they are.