Our website has a livestream for logged in users. On some special event days there are one-time guests who need to be able to view the stream as well. We give them a temporary account with this plugin. But ideally they want the account info some time ahead so they have time to distribute it (to multiple people, via slow media, in some cases even on paper). Downside is, meanwhile they have access to all the livestreams in between, and if possible we want to avoid that.

Another use case I see, is that it is secure to keep the passwordless account active for as short as possible. So if you know a support engineer needs an admin account on the 25th, you can make an account that only works on that date, even when doing it a week in advance.