By Dan Radler, L.I.S.T.D.  Ballroom and Latin, Registered World Class Adjudicator.

What factors does a judge weigh when assessing a couple's performance?

Following are 14 criteria that influence a judge’s rating in ballroom dancing. It's difficult for a judge to examine, during a live competition, all of the following points individually, since at least six couples are being judged simultaneously. Therefore, the judge must rely on the impression each couple makes relative to the others. The experienced judge, having seen and studied dancing at all levels, can quickly assess these factors collectively:

Posture
Posture is extremely important. Good posture makes you look elegant and exude confidence. It improves balance and control, and allows your partner to connect well to your body in the smooth dances. One's competition result is often directly proportional to one's postural correctness. "Persistent practice of postural principles promises perfection."
Timing

If a couple is not dancing on time with the music, no amount of proficiency in any other aspect can overcome this. The music is boss.
Line

A “line” in dance terms means the length and stretch of the body from head to toe. Attractive and well-executed lines, either curved or straight, enhance the shapes of the figures.

Hold
The hold is the correct and unaffected positioning of the body parts when in closed dancing position. For instance, the line of the man's arms should be unbroken from elbow to elbow. Also, there should be symmetry of the man's and woman's arms coming together to form a circle, which, although changing in size, should remain constant in shape so that the dancers remain in correct body position relative to each other. The silhouette of the couple should always be pleasing.
Poise

Poise, in smooth dancing, refers to the stretch of the woman's body upward and outward and leftward into the man's right arm to achieve balance and connection with his frame, as well as to project outward to the audience.

Togetherness
Togetherness is the melding of two people's body weights into one, so that leading and following appear effortless, and the dancers are totally in synchronization with each other.

Musicality and Expression
Musicality and expression are considered the basic characterization of the dance to the particular music being played and the choreographic adherence to musical phrasings and accents. They are also the use of light and shade to create interest value in response to these accents and phrases. For instance, in foxtrot, the stealing of time from one step to allow another to hover, or a quick speed of turn in an otherwise slow rumba, or the snap of a head to suddenly freeze and then melt into slowness in tango.

Presentation
Does the couple sell their dancing to the audience? Do they dance outwardly, with enthusiasm, exuding their joy of dancing and confidence in their performance? Or do they show strain and introversion?

Power
Energy is exciting to watch. I've noticed that in a jive it always seems to be the most energetic couple that wins this dance. But the energy must be controlled, not wild. For instance, powerful movement is an asset in waltz or foxtrot, but only if it is channeled into the correct swing of the body, and not just by taking big steps. The lilt of the music must be matched by the action of the body. In a waltz, for example, the dancers' body actions must clearly show the influence of the one down beat and two up beats. So the release of power into the beginning of a figure must be controlled and sustained during the rise at the end of the figure.

Foot and Leg Action
Foot and leg action are self-explanatory; however the details looked for in dance are the stroking of the feet across the floor in foxtrot to achieve smoothness and softness; the deliberate lifting and placing of the feet in tango to achieve a staccato action; the correct bending and straightening of the knees in rumba to create hip motion; the extension of the ankles and the pointing of the toes of the nonsupporting foot to enhance the line of figure; the sequential use of the four joints (hip, knee, ankle, and toes) to achieve fullness of action and optimal power; the bending and straightening of knees and ankles in waltz to  create rise and fall; and the use of inside and outside edges of feet to create style and line.

Shape
Shape is the combination of turn and sway to create a look or a position. For instance, in Paso Doble, does the man create the visual appearance of maneuvering this cape? Does the lady simulate the billowing flow of the cape through space? In foxtrot, does the man use the appropriate shape on outside partner steps to enable body contact to be maintained?

Lead and Follow
Does the man lead with his whole body instead of just his arms? Does the lady follow effortlessly or does the man have to assist her?

Floorcraft
Floorcraft refers not only to avoiding bumping into other couples, but the ability to continue dancing without pause when boxed in. It shows the command of the couple over their choreography and the ability of the man to choose and lead figures extrinsic to their usual work when the necessity presents itself.

Intangibles
Often judging is influenced by such intangibles as how a couple look together; whether they “fit” emotionally; their neatness of appearance; costuming; the flow of their choreography; and basically whether they look like “dancers”--all affect on a judge's perception and markings.

Different judges have different predilections in what they want to see and weight these factors differently. One judge, for instance, might be especially interested in technique, while another wants to be moved by musicality and expression. Although both factors are obviously important and need to be considered, these biases can result in couples receiving widely disparate markings. Couples wondering why a judge gave them a particularly high or low mark should remember that any one of the many factors listed above could be responsible. The use of a heel when a toe is warranted can just as easily hurt you in a judge's eyes as a meticulous closing of feet can help. Because the judge sees each couple for only a few seconds, anything that draws the attention, positive or negative, could very well be the deciding factor on how you are marked.

Dan Radler is a former North American, United States, and Eastern U.S. Champion, as well as United States Ten-Dance Champion.