Melbourne's public transport will soon a get a whole new ticket system, just as people seem to have finally adjusted to the present one and mostly pay their fare. Tourists and visitors excepted.
We assured that this system will be simpler and is already in use around the world. Sounds good to me. You scan your plastic ticket as you board and scan it as you disembark. Your fare is automatically calculated to you best benefit.
I can see one problem though. Crush load, or even just heavily loaded trams. If it is heavily loaded as you board, you probably won't bother scanning it in the crush. But what if you get on a tram with a normal load and it fills up? A dubious crush load figure of 140 on a tram all want to get off at once. I assume it will be just a matter of waving your ticket past the scanner, but even so, you will want to check that you aren't being charged more than is your due, at least by making sure you hear the audible signal. It sounds pretty slow to me. Of course if you are already up to the price of a daily, then you won't bother too much, but still.
It would seem Melbourne needs and has had a challenging new ticket system about every ten years. It will be interesting to see how it all comes together.