my reason for the initial drape , as Robyn points out, is to fix intersections...rotate figure and check to make sure theres no poke thru, a second drape and export is sometimes needed...you may want to check that cloth wasnt formed from a cylinder or other primitive and has a top and bottom that extends through body parts(i have found clothing items like this)..unchecking un-needed body parts is also a resourse saver , good catch Robyn...

 

:O)

Y'all have a great day.