If you're an expert tightrope walker, you're likely not gonna fall off. You can just do it without too much issue. When you're doing it over a chasm, and you don't plan on dying, you'd still probably prefer a harness though, wouldn't you?

Edit: I'm not saying C is a bad language or anything, but for important applications the safety of actually memory safe languages is vital for lower-skilled programmers and still a good assistance for higher-skilled programmers, as we're all humans and it doesn't hurt to try and avoid the mistakes we will eventually make.