Lead Funnels

Recently I heard Brooke mention somewhere that getting your lead funnel to work is super fun and takes many many tries! Wondering exactly what she meant by that. Is it the technology that she was referring to (like getting the technology all to work and talk to each other). Or is it figuring out what people will respond to in order to provide value to people and then they enter your lead funnel? Or something else??
The reason I ask is because I have downloadable assets on my website that people visit, I can tell they are clicking on the page, but they are not putting in their first name and email to download it. Therefore my lead funnel is not a lead funnel. LOL! No leads! Assuming I need to tweak it until someone starts downloading something! And yes I tested the funnel and it works for me and I even asked the IT support team and they show its working on their end 🙂 Thanks!