Explode problem

Hi guys
I encountered an problem, why the outermost circle is not exploded? Does anybody know what is the reason? grateful

explode.gh (85.2 KB)

Because it is an arc, not the polyline like other crvs.

Thank you for your reply, so how can I make the outermost circle also explode?

You can’t explode it as it is one segment only. If you want this curve to be fragmented you can divide this curve into segments by number or length and then explode it.