It has to do with the order in which property nodes take effect in an Open Inventor scene graph, a very important concept to understand when using Open Inventor. Nothing described above the node will be effected. To limit the range of an effect, enclose the property node and the nodes you want it to act upon in a Separator node. That way the effect only lasts until you reach the bottom of the enclosing Separator .
Geometric transformations accumulate in effect.
In other words, if you have two RotationXYZ nodes in your file positioned one right after the other, both rotations take effect. The first rotation in the file takes first, the second rotation takes effect after the first one. Non-geometric properties that control object appearance override each other. In other words, if you had two Material nodes in your file positioned one right after the other, any colour specified in the second node would override the colour specified in the first node. It is an artifact of the process by which Open Inventor uses the scene graph to construct the image you see in a viewer.