the comment was not dumbass at all, besides, it has recently mentioned about layout objects, somewhat visible to find out with search.
But because you probably won't use that search anymore, I tell you a tip:
Use Z-factor making an object on air, but still having it on ground, you will notice this by Cyan dot, object is not valid on ground, but can be still attached indirectly by decreasing/increasing Z-factor.
Why this?
When object is on float ( cyan dot ), objects can cross each other.