Marketing tells you that you need to be the first at something for brand recognition. Once a term has been ingrained into society how do you compete with that? You could ask my mom, who never uses computer, if she knows anywhere to auction off an item 'on the computer' and she'd likely say eBay. You can't simply go head-to-head. You can't simply add more features. You have to accept being #2. Most people probably can't think of a way to spin another auction site, well enough, so they don't bother.
you have to make something that is so just straight up better in all ways that it brings everyone over en masse and in a hurry.
I don't think I need a complete replacement of all functions to be engaged to sell. I just need the essentials.
I'm a seller. Is it really necessary to be better in "all areas" to beat the incumbent?