Resolved Quaternion returning wrong value.

First time posting here asking for help. The thing is, I already resolved my issue by using another code.
But here is the new issue, I don't understand why my code didn't work - and it'll be an issue later on if I'm missusing this as is.

Scenario:
I'm making a little minigame. Several rotating cylinders with an opening in them. Every cylinder moves in a different direction, and at different speeds. I'm very happy. But then I realize my code for making their starting rotation randomized doesn't work...
This is what I had:

Code (csharp):

1.  
2.     [SerializeField] private Quaternion initialRotation;
3.     [SerializeField] private Quaternion randomStartPos;
4.     [SerializeField] private bool spinningRight;
5.     [SerializeField] private int spinningDir;
6.     [SerializeField] private float spinningSpeed;
7.    
8. private void Start()
9.     {
10.        //Setting and saving a random Quaternion
11.         randomStartPos = Random.rotation;
12.        
13.        //logic to handle if it's going left or right, and at what speed.
14.  
15.         spinningRight = (Random.value > 0.5f);
16.         if(!spinningRight)
17.         {
18.             spinningDir = -1;
19.         }
20.         else
21.         {
22.             spinningDir = 1;
23.         }
24.  
25.         spinningSpeed = spinningDir * Random.Range(0.3f, 1.0f);
26.        
27.         //This is where the issue is. It won't let me use the information from the quaternion. It just sets Z to 1.
28.  
29.         transform.rotation = new Quaternion(0,0,randomStartPos.z,0);
30.  
31.         initialRotation = transform.rotation;
32.     }
33.  
34.    
35.  
36.     private void Update()
37.     {
38.         if(isSpinning)
39.         Spin();
40.  
41.  
42.     }
43.  
44.     private void Spin()
45.     {
46.         {
47.           transform.Rotate(new Vector3(0f, 0f, spinningSpeed));
48.         }
49.     }
50.  

I ended up using:

Code (csharp):

1.  
2. transform.rotation = Quaternion.Euler(0,0,Random.Range(0,360));
3.  

Mainly posting it for anyone who googles this specific thing. But for myself, I'm asking this because I wanna know what I did wrong.

Thank you.

 

The .x, .y, .z and .w fields of a Quaternion are NOT ANGLES.

Do not molest them unless you have a math degree. They are Quaternion internals.

Perhaps you want the .eulerAngles.z property?

Whatever it is, keep this in mind as you proceed:

https://starmanta.gitbooks.io/unitytipsredux/content/second-question.html

 

Thanks! This answered exactly what I needed.
Now I don't have to worry about making that mistake, and I know why!