Warping is a stylistic or communicative form of Shaping that diverges from a grounded or seeking alignment. Bowing does so by forming a long but extend arc to keep the spine safe. Warping is a more catchall term incorporating for example twists of the long bowed arc or multiple arcs.
The reason we use an extended arc is to maintain safety. The body and especially the spine do not generally appreciate tight bends under strain as the force is applied to the joint with leverage. Instead engagement into the elongation allows force to be distributed. In theory each individual bend in the body can be protected with intentional muscle engagement to prevent strain. However especially in a lead follow dynamic where partners are not always immediately sure where and how external force will be applied this becomes impractical outside of the highest of technique specifically in the areas of kinesthetic awareness and mutual trust, connection and understanding between partners. Simply it is too much to think about.
Thus Bowing and warping allow much play towards shaping ideals while still allowing an elongation understanding as a catchall for injurious motions.
Bowing and warping are arguably one of the two ways to counter Stirring though there are limits.
Topics for Further Consideration:
Shaping
Shaping Lead
Pillar of Body Mechanics
Head & neck Positioning
Zouk
Muscular Differentiation
Safety
Stirring
Center of Weight