Combination of static review and dynamic notification
FOMO (not an insult!)
I say this because Facebook once blocked an ad of mine db center whatsapp number where FOMO was written, justifying it as an offensive word and even after reviewing it was not passed. Meh!
FOMO is the acronym for Fear of missing out... the fear of losing or being left without something , which applied to Lead Generation, for example the sale of classroom courses, can be the lever of scarcity - the fear of few places left - or if applied to eCommerce the scarcity of remaining items on sale or in stock.
Putting a little spice in the user's ass by making him understand that "now or never" he can have that particular thing, helps to shorten the infamous funnel and make our campaigns more profitable.
Should I tell you that the data must be truthful and that deceiving your target in the medium to long term is detrimental to the reputation of the Brand? Think about the discounts on Poltrone e Sofà: do you still believe that they are on sale? I don't think so... Do not lie!