Unity - Child Rotation and Scale error

Question

I'm saw some wierd responses from Unity when I tried to do these actions :

1- I've created a Plane, simply rotated it (-32,-19,-56) and scaled it (3.21,1,2.43)

2- I've created a child cube for that plane and rotated it (-30,39,-78) and scaled it (3.54,4.8,6.42)

This is the final result in editor :

Did I do something wrong???

Why collider and renderer performing differently??

Is this a Unity bug? I'm currently using Unity 2017.3.1p1

Answer 1

Yes, it is some kind of bug.

To avoid it, don't child the objects directly to a non-uniformly scaled parent. Instead, child this non-uniform object (the cube) to an empty object, which will be the parent of the plane too.

Since an empty object is scaled 1,1,1, childing other objects to it don't cause this problem.