Can anyone answer this question about the Single Transferable vote system?

[ItsAllGoingToBeFine]

Imagine there are 4 candidates A,B, C & D

I really like candidate A, but B will do in a pinch. C and D are both utterly shit, but if push came to shove then C would be marginally less reprehensible.

So obviously my first choices are:

1st - A
2nd - B

Now imagine A, and B get all the votes they need, so my vote would be potentially transferred. If I additionally put

3rd - C
4th - D

Then my vote transfers to C and then D if C gets enough votes.

But what happens if I leave my third and fourth choices blank? Does that just mean one less potential vote for both C and D? Does your vote just cease to exist if you don't indicate a preference?

Yes if you stop expressing a preference your vote just stops being counted. So in a runoff between C and D you would be deemed to be an abstention

Yup - as peukpikuzo says, you only need to put down as many preferences as you want.

But you the numbers have to be in sequence: as in 1,2,3 (if there were, say, 5 candidates and you only had preferences for 3 of them) but not 1,3,5. If you did that, only your first preference would count.

Thanks both!

There is no point putting down a 4th vote if there are 4 candidates. If your 1st 2nd and 3rd choices are all eliminated then #4 is the winner. If C is awful but marginally less awful than D they might as well have your 3rd vote.

I was in a situation like this once where there were 9 candidates, only 2 of which I had any confidence in and the rest all had varying degrees of probably-homophobic awfulness which I felt I had to carefully assess exactly how awful each was so I could put them in order of ever-increasing awfulness.