We encounter funnels in a lot of things that we do - hiring candidates for jobs, picking a show to watch or a podcast to listen to, etc.

When designing our product, process or interaction, we can design it for something that looks like a cone (wide at the top and narrow at the bottom) or something that looks nearly cylindrical (nearly the same size at the top and at the bottom).

The first design assumes we will witness a lot of drop-off along the way (like the image above). We need to reach a lot more people than the number that we want at the end of the funnel (a 100 times more in the image). 

The second design assumes little to no drop-off along the way. Rather than reach a lot of people, we need to convert every person that we reach out to.

These are two very different approaches and our approach and strategy will be drastically different depending on the choice we make. 

The good thing is, they are both valid choices.