I have a methd to log the angle diff:

```
protected override void LogDiff(Quaternion v1, Quaternion v2)
{
var direction = new Vector3(0, 0, 1f);
var d1 = v1 * direction;
var d2 = v2 * direction;
var delta = Vector3.Angle(d1, d2);
var dist = Quaternion.Angle(v1, v2);
Debug.Log(Time.frameCount + " -()-()-Calibrate diff Quaternion.Angle=" + dist + ", Vector3.Angle=" + delta + " | " + v1 + " - " + v2 + ", " + v1.eulerAngles + " - " + v2.eulerAngles);
}
```

Then I got his result that I can not understand, Quaternion.Angle returns wired value:

```
2143 -()-()-Calibrate diff Quaternion.Angle=2.451461, Vector3.Angle=0 | (0.00000, 0.10456, 0.00000, 0.99440) - (0.00000, 0.10456, 0.00000, 0.99440), (0.00, 12.00, 0.00) - (0.00, 12.00, 0.00)
5740 -()-()-Calibrate diff Quaternion.Angle=2.868992, Vector3.Angle=0 | (0.00000, 0.10456, 0.00000, 0.99436) - (0.00000, 0.10457, 0.00000, 0.99436), (0.00, 12.01, 0.00) - (0.00, 12.01, 0.00)
9338 -()-()-Calibrate diff Quaternion.Angle=3.252124, Vector3.Angle=0 | (0.00000, 0.10457, 0.00000, 0.99431) - (0.00000, 0.10457, 0.00000, 0.99432), (0.00, 12.01, 0.00) - (0.00, 12.01, 0.00)
12924 -()-()-Calibrate diff Quaternion.Angle=3.571501, Vector3.Angle=0 | (0.00000, 0.10458, 0.00000, 0.99427) - (0.00000, 0.10458, 0.00000, 0.99427), (0.00, 12.01, 0.00) - (0.00, 12.01, 0.00)
16512 -()-()-Calibrate diff Quaternion.Angle=3.867012, Vector3.Angle=0 | (0.00000, 0.10459, 0.00000, 0.99423) - (0.00000, 0.10459, 0.00000, 0.99423), (0.00, 12.01, 0.00) - (0.00, 12.01, 0.00)
20092 -()-()-Calibrate diff Quaternion.Angle=4.153012, Vector3.Angle=0 | (0.00000, 0.10460, 0.00000, 0.99418) - (0.00000, 0.10460, 0.00000, 0.99418), (0.00, 12.01, 0.00) - (0.00, 12.01, 0.00)
23674 -()-()-Calibrate diff Quaternion.Angle=4.420554, Vector3.Angle=0 | (0.00000, 0.10461, 0.00000, 0.99414) - (0.00000, 0.10461, 0.00000, 0.99414), (0.00, 12.01, 0.00) - (0.00, 12.01, 0.00)
27224 -()-()-Calibrate diff Quaternion.Angle=4.667782, Vector3.Angle=0 | (0.00000, 0.10462, 0.00000, 0.99410) - (0.00000, 0.10462, 0.00000, 0.99409), (0.00, 12.02, 0.00) - (0.00, 12.02, 0.00)
```

I know you may say there's float error, but why so such big, and getting bigger and bigger?