What is a key best practice for Online Video ads when the objective is to drive sales?

For online video ads aiming to drive sales, visual product demonstration is paramount. Viewers often watch videos without sound, especially on mobile devices or social media feeds. A strong visual demonstration clearly shows the product's features, benefits, and how it solves a problem, making an immediate impact even without audio. Consistent narration throughout or narration that tapers off can be less effective if the visuals aren't compelling enough on their own. While narration can complement visuals, relying solely on it or making it the primary communication method risks losing engagement from viewers who aren't listening.