From the docs, in Maya4.5/docs/en_US/html/UserGuide/Cloth/Designing27.html
When you create a garment from curves, Cloth creates a mesh with varying sizes of triangles that are randomly distributed. The mesh has no regularity or stress lines. This creates more natural folds.
In addition, if you change the resolution of a garment after simulating, Cloth can update the geometry without resimulating. However, you need to simulate for the cloth to move with the new resolution.
All the constraints in Cloth apply to garments.
Cloth objects
You create cloth objects from polygonal shapes or NURBS shapes. The original shape is hidden and the tessellated cloth shape is displayed. The original shape and the cloth shape are grouped under the object's transform.
With NURBS objects and certain procedurally-generated polygonal objects, you can get artificial stress lines caused by the regular tessellation.
If you change the topology of the polygonal object after simulating, you have to resimulate.
Only the transform, field, and mesh constraints work on cloth objects. If you change resolution, you must reattach these constraints.
Important!
Cloth objects originating from NURBS surfaces are inherently unstable in stressful environments due to their regular tessellation. Regular tessellations contain unnatural biases for bending, which can cause the surface to collapse when bent in those directions. We recommend that you use a cloth garment instead of a cloth object if the cloth will be put under stress, such as folding or significant stretching.