Whoever put the one in our local park growing up must have been a sadist, or at least thought "you know what? There's too many kids running around these days. We need to fix that." The top surface was slicker than a greased up pig with even the slightest hint of moisture. The top plate hung over the outer edge just a little, and was razor sharp. But the part that really took the cake? The center pivot for it was poured into a huge cement slab that extended out beyond the platform. That meant when you inevitably get flung out from it, more than likely already bruised and bleeding, you are landing on concrete. I'm amazed they didn't wrap it in barbed wire and put it next to a rocky embankment leading down to a highway.
In fact I bet that playground equipment was sold by this guy: