I parented objects to my armature and applied weight painting. I started off on a different part of the model, where the weight painting wasn't the entire object.
I thought that was the problem, but with the example I have (in the video below) it is with a singular object that is 100% red in weight paint. Upon rotating the bone it is weighted to in pose mode, the object does not rotate all the way with the bone. And when the bone reached 180 degrees, the object flips for some reason.