The trick is not to over cook the meat. If it turns brown/black, you have basically burnt it. Keep it golden and it will be soft.
Edit: Learnt this trick from Aussies, who love BBQ all day every day. Sadly, Pakistanis burn meat most of the time while BBQ. Overcooked meat is what is programmed into our brains. BBQ meat is meant to be cooked at low temperature for longer periods of time, and turned frequently to avoid overcooking of one side.