Trying to rotate a 2D image over time to a specific angle, but it's rotating its Y value every time

Questions & Answers
1

I have a 2D image that I’m trying to rotate to line up over a selected button. I’m using Quaternions, but despite only changing the Z value, it’s rotating the image’s Y value by -90 degrees and screwing it up for reasons I can’t figure out.

public RectTransform pic

 //Rotate the image over time to be on the selected button
    IEnumerator RotatePic(int selected)
    {
        float moveSpeed = 0.1f;
        float dest = 0;

        //Set the right angle for the right button
        switch (selected)
        {
            case 0:
                dest = 55;
                break;
            case 1:
                dest = 30;
                break;
            case 3:
                dest = 10;
                break;
            case 4:
                dest = -10;
                break;
            case 5:
                dest = -30;
                break;
        }
              
        while (pic.rotation.z < dest)
        {
            pic.rotation = Quaternion.Slerp(pic.rotation, Quaternion.Euler(0, 0, dest), moveSpeed * Time.time);
            yield return null;
        }
    }
2

Try flipping the y and z axes when moving from Vector3 to Vector2.

    public Vector2 FlipV3toV2(Vector3 direction)
    {
        return new Vector2(direction.x, direction.z);
    }