The ACT Elections factsheet on Hare-Clark describes our vote-counting system. It claims to be a single transferable vote method.
The counting is based on a quota, which is the number of votes a candidate needs to get elected. (The factsheet describes how a quota is calculated.)
If you vote ‘1’ for a popular candidate who gets more than a quota, your vote is counted twice – once when you help the candidate get a quota, and again when excess votes are distributed at a reduced value. You also support someone you didn’t vote for because your vote helped create more than a quota that is then redistributed to everyone’s 2nd and later preferences – even if you only put a ‘1’ on your ballot paper.
What if you vote ‘1’ for someone who doesn’t get a quota? Your vote is distributed according to your preferences at their full value. Eventually it will end up with someone who gets a quota. If you didn’t number all the boxes, you might run out of preferences before you can elect a candidate: your vote is exhausted.
If a candidate gets a quota after getting reduced-value preferences from another candidates, any ‘1’ votes for them before then are safe. They stay with the no. 1 candidate and are no longer counted (other than to establish the quota). They still enable support for other people’s preferences, even though only the new votes from other excluded candidates are redistributed.