It could clean then produce cotton tenfold the time it would take a normal human. It had a negative impact because since it would clean cotton so fast many plantation owners bought more cotton (the more the cotton the more the money). But more cotton requires more harvesters so these plantation owners also would buy more slaves. This of course was not good since this commenced through out the whole country causing a massive spike of slaves to be purchased. If you have any more questions just ask :)