There's a national election here on the 7th of May. That'll be fun, I always enjoy the process. I never reveal who I vote for, but I also definitely won't vote for the two leading parties (ANC and DA) on principle; I think a two-party democracy is as pointless and doomed as a one-party democracy. With that in mind, I'd like to add my objections against the Vote No campaign, which claims that the way to oppose ANC corruption is for voters to spoil their ballots, i.e. to vote for no party.
Mathematically, this is bullshit. A spoiled ballot actually helps whichever party is already in the lead.
Consider a nice, simple situation in which there are only 4 voters. Let's say 2 of them vote for Party X. That's already giving X a really solid start; whatever the other 2 voters do, X has at least 50% of the votes. If the other two voters vote for Parties Y and Z, X gets 50%, Y gets 25% and Z gets 25%. Simple, yes? It's a cake cut into four slices, and X wins 2 out of 4 slices.
Now let's say our Z voter instead spoils the ballot. This is like throwing away one slice of the cake and pretending it was never there. Now X gets 2 out of 3 slices (66.7%) and Y gets 1 of 3 slices (33.3%). If Y spoiled the ballot too, then there would only be 2 valid slices of cake on the plate, with 100% of them going to X.
This is the situation with South Africa's elections. Only valid, unspoiled ballots are counted as part of the whole cake. Spoiled ballots are junk. Any opposition voter who spoils their ballot is in a very real sense just feeding the ANC a greater percentage of parliament. And if you're like me and don't like the idea of a two-party hegemony, then failing to vote effectively for an alternative party, also gives the DA a lesser but still real boost.
So, vote. Vote well. Vote non-No.