Not sure exactly what you mean... See, you may throw a jab not so much to land it but to see how he plans on avoiding it. If you jab with a bit of shoulder and hip in it, while pushing off the back foot its more a straight left hand. Are you looking to draw a counter right, or doubling up to discourage one? Jabbing your way in or backing him up with a jab? Using it to take the initiative or to counter and disrupt? The rising jab of Burley, Moore and others is a very damaging counter against a guy who really steps with his jab. Never jab down or across your body. You don't need to land every one, and even if the jab misses throw the right hand/hook, or whatever anyway. Sometimes not jabbing is best- Arguello v Mancini comes to mind. Mancini hoped to slip the jab get in hit the body get out but Alexis didn't jab much or committ much when he did forcing Ray to advance and retreat under fire. Watch Ricardo Lopez, Toney, all the pros. Try to think what they are thinking as you watch what they do and don't do