So about clear times for tanks

I don't know why, but doesn't it seem almost consistent that many tank Junglers lately rush purely defensive options for their tank sets?

No you did not read that wrong, I mean they rush items like Randuin's Omen or Banshee's Veil, items that do absolutely nothing to help their clears. They don't build Sunfire's Cape, a good all around item with aoe clearing abilities, they rarely would rush something like Thornmail against AD Heavy teams, hell, ignoring Juggernaut, I find it rare to see heavy investment into CDR until the second or third completed item.

I don't know why, but this bothers me really bad. Especially when one begins to complain how hard it is for Tank Junglers to clear the Jungle, I really just don't understand why they almost flat out don't invest in any items that would improve clear time even when it matters the most.