How do you know if a video will perform better than an image? Instinctively, a video is more engaging. It should perform better. The truth is you don’t know until you test it.
Trying to predict your campaign’s performance on day zero is a waste of time. If you have never tried that funny video, or clever image, with that specific audience, you don’t know how it will perform.
That’s why agencies and media analysts can’t give you an accurate target CPA number. They can’t tell you how changing a variable will impact results. They can only predict if they have data: if they’ve worked with your competitor, in your industry, with your target audience, and a specific channel.
The reason why so many people give up on Facebook Ads after they’ve boosted a post is that the results are never what they would’ve expected. They will say things like “it doesn’t work,” “it’s not for my brand (for me),” “it was a waste of money.”
You can only project results on levers (audience, creative, channel, device, day, month, you name it) you already have historical data for.