It's the simple things imo. I'm a newbie and I'm definitely not complaining, but there's quality of life issues most casuals won't bother with. Starts with the search function. I'm sure it works beautifully for those who understand it, but I don't. Finding communities seems kinda awkward and then there's the issue with the URLs. With reddit I can just remember the /r/whatever and share it without having to copy/paste some hive designator. There's bookmarks, sure, but that also falls flat as soon as I use another device. So I'm digging around again. Take like 30 seconds to be fair, but most people just won't do that.