I dunno. I think you want to make efforts to get at what the voters actually want, and that means making some allowances for voters being, y'know, fallible humans.

Have a look at the "butterfly ballot" used in Florida in the in 2000 presidential election:

Now, it's pretty clear to me, looking at that, that the top hole is a vote for George W Bush, the hole below that is a vote for Pat Buchanan, and the hole below that is a vote for Al Gore. But it's also obvious to me how a voter could think that the second hole is for Gore, as the listing on the left side of the ballot has Gore listed just below Bush. I wouldn't make that mistake here, but it's plausible to me that people would. And indeed, people did. Buchanan got a LOT more votes than his polling would lead you to expect; and while this was still a small number of overall voters, it was more voters than the margin in multiple counties, including Miami-Dade. And Florida had enough electors, and the national election was close enough, that how Florida went decided how the whole country went. That is, these few people (less than 2000) making this mistake may have been a deciding factor in the national election of George W. Bush.

So while, yes, it's the vote they cast, and if they can't handle something as simple as voting then maybe that's on them... it's not like it doesn't matter. We should want the outcome of the election to reflect the will of the voters, and so it makes sense to make some effort to make it easy for them to vote for the person they actually want.

Elections aren't usually close enough for this kind of thing to matter. But it sucks when it does.