Chester Skinner built a tumbling machine used to clean and finish metal parts. Power to the machine was controlled by a switch manufactured by Square D Company (defendant). The switch was connected to the machine’s motor by wires with “alligator clips” on the ends. Operation of the machine required manually reversing the direction of a rotating drum, which Skinner or a coworker did by shutting off the switch, disconnecting two alligator clips from the motor, and reversing them. Whenever the machine was on and hooked up, it either rotated or made noise. In February 1986, Skinner was working alone when his wife and two other women in the next room heard him call out. They found him holding an alligator clip in each hand with live current flowing through him. Skinner was able to remove one clip and flip the switch to the off position. He then died. Representatives of his estate (plaintiffs) sued Square D, contending that its switch was defective in that it did not always indicate clearly whether it was on or off. Plaintiffs alleged that such defect caused Skinner’s death. They presented evidence that Skinner was a careful worker, and they theorized that the accident resulted when the machine was on but the wires were unconnected so that the machine was not moving or making noise to indicate it was live; Skinner was thus led to believe by the defective switch and the state of the machine that it was not on. Square D moved for summary disposition, contending that even if the switch was defective, plaintiffs had failed to establish sufficient evidence that such defect caused Skinner’s death. The trial court granted Square D’s motion. Plaintiffs appealed.