The dead-stop dumbbell row cleans up a lot of technique faults, probably because it forces people to slow down and gather themselves with each rep.
While maintaining a neutral spine position throughout – the body should make a straight line from the head through the lumbar spine – start with the dumbbell resting on the floor. Grab the handle and crush it, gripping it as hard as you can. From there, row the dumbbell by bringing your elbow towards the hip, not just going straight up and down.
Effectively, you'll be "pulling through the elbow," finishing at the top by retracting your shoulder blade towards the midline of the body. To finish, return the dumbbell to the floor, coming to a complete stop. Pause for a second or two, and repeat for the desired number or reps.
For those with shorter arms, you may want to grab an aerobics step or a few mats to place on the floor to decrease the range of motion.