Joining Curves with an undesirable result

This might bit a silly question but I recently started playing around on grasshopper and I hit a dead end.

I aim to find and connect all possible triangles from an 5 sided polygon. I have managed to find all vertices, create all necessary lines and have them in the correct order. But joining them together instead of 5 expected triangles I ended up with 2 and cannot figure out why is that happening.

Brainstorming #2 - Confluence Park - (23.3 KB)
Brainstorming #2 - Confluence Park.3dm (26.0 KB)



There are all sorts of ways. Attached are a few different options to help get you started.

Brainstorming #2 - Confluence Park - (20.2 KB)

Thank you Adam,

Needed some other perspective to get me going. So much clearer!

Much appreciated,