The 90-minute policy at Stack Overflow combined with the exhaustion of IPv4 addresses has already caused problems for users behind network address translation (NAT). When you have the same IPv4 address as another user of Stack Exchange, it can be tough to squeeze in your question when others are waiting for the same 90-minute window to reopen so that they can squeeze in their own questions. See, for example, the question "[Error — 'you can only post once every 90 minutes' but I haven't posted in days](http://meta.stackoverflow.com/q/259941/2738262)" by Bryan on Meta Stack Overflow. * Some people's only Internet access is at a school, office, or public library, which typically has one Internet access subscription with one IP address. * Some countries have so few IPv4 addresses that home ISPs put several subscribers on a [carrier-grade NAT](https://en.wikipedia.org/wiki/Carrier-grade_NAT). Comments to that question's answer recommend subscribing to cellular Internet access and asking the question through that connection. This ignores two realities: * I do not own a smartphone. I or anyone else in a situation like mine would have to subscribe to Internet access twice, which costs more money every single month. Now you have to pay more just to use Stack Exchange on top of what you already had to pay to access the Internet. I thought getting around having to pay for ExpertS-exChange was why the Stack Exchange network was created in the first place. * Cellular ISPs almost always use carrier-grade NAT, and this cellular ISP may already have Stack Exchange users on it, leading to the same problem as before. Thus without the ability to ask or answer questions before 125 reputation, a new user would have to farm rep by suggesting edits and have 62 accepted just to be able to use the service as intended.