Wine glasses are almost all thin glass and slender stem, and that stem is the weak link that snaps with the smallest sideways knock. Stemless and everyday glasses are hardier but still chip at the rim. Wrapping each glass, bracing the stems, and standing them in a divided box keeps a set of wine glasses intact through the move.
Pro tip: Cell boxes with individual compartments are made for stemware and are worth using.
Watch out: The stem is the weakest point. Wrap and brace it first, and never let a glass bear weight on its stem.