I have done a complete 360. Always used to prewash. Then came another 10 years and stopped with the exception of dark navy and any shade of bright pink and all reds. I'm back to pre-washing most again, except for whites and pastels. Am absolutely amazed at the amount of dye that comes out, whether I've paid $2.97 or $14.00 a yard. Also, so much sizing that water in the basin bubbles as if detergent was applied. I'm retired so I have the time to pre-wash, then iron but it is an enormous pain in the butt.