James P. Womack

Lean production is lean because it uses less of everything compared with mass production — half the human effort in the factory, half the manufacturing space, half the investment in tools.

The truly lean plant has two key organizational features: it transfers the maximum number of tasks and responsibilities to those workers actually adding value to the car on the line.

Muda is specifically any human activity which absorbs resources but creates no value.

The critical starting point for lean thinking is value. Value can only be defined by the ultimate customer.

Most activities that we think of as value-creating are actually muda, and most of the rest are necessary to support the value-creating steps.