Google has some amazing ad insights. They have departments devoted to reviewing best practices to ensure people continually place ads on their network. If you sign up for their digital marketing emails you’ll receive a bunch of great stuff.
Including this video breaking down what works. Everyone always says that ‘size matters’ but it seems like what matters is giving people what they want, then if you keep giving them other cool things they’ll keep following you.
The statement in the video was to give them pie first, a reason to stick around, the punchline, whatever, then give them the story leading up to it.
So if you’re wondering about length, that just matters how much engagement you want. Focus on giving dessert first, then give them a story and they’ll stick around longer.