Form and function while closely related are different in definition and practice, however both are incredibly important when developing an ad/website/etc. Form, the foundation of your ad/website/etc, consists of the little things that make a big difference. This is the look, the feel, and the overall design of your product. The function is how the end product performs or functions. You can’t have one without the other.
From a creator’s point of view, it is a bit difficult to value form or function over the other. However, if I had to choose, I would pick form. I truly believe that consumers, especially those between the ages of 18 and 35, engage with content because they want to, not because they are being forced to. That being said, creating a website or advertisement that is aesthetically pleasing to look at and overall different than anything they have seen before is crucial to bringing in traffic. I also think that young consumers (again, 18 to 35) for the most part prioritize the form of a website. If we were to be speaking in terms of older adults (40+) they might have a bit more difficulty navigating a website and couldn’t care less about what the website looks like so long as they achieve what they set out to do. I for one know that my grandparents and parents for that matter sometimes struggle when websites don’t blatantly show where to click to either place and item in a cart, checkout, or search for something. In that instance, function would be valued more. All in all, it truly depends on your target audience and whatever works in their favor.