I found myself inadvertently mousing over to the red swoop in this ad every time I saw it today.
I realized that my brain was catching the bit of red in the thin band of blue with white letters and impulsively moving the mouse over to click it.
I don’t know if the designer of this ad did this on purpose, but it seems to stimulate a pavlovian click response. The little rush of reward juice I get when we see that someone has “liked” a post or comment of mine or responded to something I’ve done on Facebook has subtly wired a “desire to click” when I see a pattern that matches the Facebook header when it’s pregnant with notifications.
I’m not sure if this response is unique to my internet addled brain, but I bet this ad has an abnormally good CTR compared to similar ads that don’t mimic such an emotionally rewarding click.