STV eliminates candidates (and transfers their votes) until someone hits quota and win a seat. Then that winner's leftover votes are redistributed according to the next preference on those vote papers, and the process is repeated until there are no seats left to win.
One of the complaints about STV is that someone who is no ones first choice can get eliminated, even when it might turn out that they would get many second choice votes later on.
What happens if, after eliminating candidates enough times for someone to win, then in the next round those candidates are put back into the race, so can receive next-preference transfers?
It seems to make the counting process more complicated, but if you're doing this electronically, not devastatingly so. It puts candidates back in to receive transfers even if they weren't good enough to stay in the first round election.
What led me to wonder about this is some previous musing about proportional representation in the hereditary peers bit of the House of Lords, which is a bit like a stretched-out-over-time system that puts candidates back in for each seat.