The ski manufacturing process uses heat to laminate the various layers of the ski. The cooling process causes slight variations in the flatness of the base to develop.
These changes apparently continue after the factory tune-up. I have had several pairs of new race stock skis that have come a warning sticker on them advising that they are not to be used before a tune-up.
My understanding is that in most cases new skis should be given a light base grind to restore the flat base. Then you want to start with a one-half degree bevel on the base edges and a two-degree bevel on the side edges. The put on storage wax.
Then wait patiently for winter. Oh, and I almost forgot - its already time to start dryland training!