Lean’s “blind spots” are described in detail in EPA’s Lean and Environment report.

Say:  In this example the lead time for first piece of with the batch process is 21 minutes. That 21 minutes is reduced to just 3 minutes if the batch size is reduced from 10 to 1.   You will also notice that the large batch size results in lots of WIP.  Look at the piles of WIP between operations A, B, and C in the 10 piece batch example.  Does it remind you of our company Buzz  Electronics? It allows defects to pile up between operations, without being discovered by the next process (internal customer).  By contrast in a small batch operations, problems are likely to be discovered much more quickly.

Basically, we take raw materials from the earths crust, and push them into some shape so they do some function we want them to do. But unfortunately, we arent very efficient.  According to the national academy of sciences…

To make a product, we waste 93% of the materials…and even then, 80% of the products we make don’t last for more than 6 months…. The rest of the materials are like our old friend, the tailpipe smoke, or hazardous metals in our water, or solvent disolving slowly into the atmosphere, or just plain old scraps that become piles of garbage. So think of something you own,…imagine you had to carry around all the coal, solvents, metals and other materials that it took to manufactured.  How big would this pen be? Now, when I am done with my pen, I throw it, and the other 93% of it’s mass into the atmosphere, and pull more out…and we are getting better and better at it.

Newspaper example…for instance, it takes a certain number of acres to grow a tree, and run a paper mill, and produce the chemicals for the ink…you can take all these and estimate how many acres it takes to make your morning paper…Lay the paper out on the floor…if it wasn’t recylcled, it takes about the area of the sheet of paper…

People use the footprint to identify where there impact is.  This gives them a clue about what they are doing with the environment.