If you can improve an answer, you could always give a new answer? > The point is that SO is missing out here. Unfortunately, if comments were open to all init

If you can improve an answer, you could always give a new answer? > The point is that SO is missing out here. Unfortunately, if comments were open to all initially the site would quickly fill with “me too” comments and other things that would fill the page with low quality content that would be effort to moderate. This already happens to an extent with answers. My point being that the potential gain from automatically open comments may be less than the potential hassle from less useful users. Balancing these matters is difficult, many places get it even more wrong than SO and related sites do, and there is probably no perfect answer that doesn't put off some useful contributions.