A workcell is an arrangement of resources in a manufacturing environment to improve the quality, speed and cost of the process.
They are based on the principles of Lean Manufacturing as described in The Machine That Changed the World by Womack, Jones and Roos.
For instance, lean workcells must be designed for minimal wasted motion, which refers to any unnecessary time and effort required to assemble a product.
Excessive twists or turns, uncomfortable reaches or pickups, and unnecessary walking all contribute to wasted motion and may put error inducing stress upon the operator.
Small lot sizes usually increases transportation waste, but this can be eliminated if machines are back-to-back in a workcell.