To be fair, the lean concept often makes sense. You can get workers involved by soliciting and developing their ideas, so it can be a motivator. Because they contributed the ideas, they should be committed to their success. You can publish the results as they occur, so folks know how they're doing in achieving the goals, further motivating them to do good.
That's not bad. Sometimes worker ideas pay off. But, like quality circles of an earlier generation, sometimes they don't. The problem with lean manufacturing is that it focuses on the work that people do on the shop floor. In its most beneficial form, lean manufacturing decreases the number of people needed to get the same output and shrinks in-process inventories. There's nothing wrong with either result, but it's rarely easy and the results may not amount to much.