Part of the debate that occurred in Parliament here was on the fact that previously we had the ability for citizens to vote “1” above the line in the Senate and their vote would then to be transferred according to a very complex preferential system with each party. This system was linked to what some people perceive to be odd results, with some senators being elected with a very small primary vote.
Parliament mandated the changes to the Senate voting system to give people more control over where their preferences went. That's probably a better way of describing it.