bro there is many reasons your cuttings will do this..Are they dieing? did you get air in your stem when you cut it? did they have a dom over them for humidity? do you spray them? did you over water/ under water? some cuttings look as if there dieing when there pushing roots becouse they use all there energy up to do it!could be so much bro read up on some other forums and see what might fit your prob..more ifo from you would also help us help you