My goal.

[AceInfinity]

Also, make sure you're not just "dropping" the weight after each rep, make the motion continuous. Slow 3-5 seconds up, 2 seconds to lower, but at the top of each raise and at the bottom of each lower in your reps, if you're at the bottom position start moving up immediately, and vice versa, don't take that rest before powering out in your next rep. Continuous motion will make it harder for you which makes the reps more efficient. Make sure your elbow is locked at your side to when you do it. I've seen some people try to jerk the weights with their shoulders somehow to get it up on the last rep, don't do that. Instead, either get someone else to lightly assist you in doing the last rep by placing a finger below the weight helping you lift it JUST enough so that you can barely raise it. This will maximize your motion but also ensure that you are doing most of the work. If you can't get someone else, then instead hold the weight up, and lower the weight as slow as you can, this will keep the tension for your muscles to work, but also keeps the motion, just in reverse though.

You can do the same with pull ups. If you can't do another rep, jump up to the top and slowly let yourself down. It keeps the motion so that all of your muscles that have to work to pull yourself up are working in reverse order, but you're still getting the benefit of a pull up, on a minor scale.