Why Not Manufacture in Easy Batches?

During a workshop, a manager resisted the idea that batches are always to be avoided if possible.  He used the example of paying his bills by check (this was before the days of online bill-paying). It was easiest for him, he said, to sit down at the kitchen table, open all the bills and take them out, write all the checks, stuff all the envelopes, put stamps on all the envelopes and drop them in the mail.

I asked the group if there was anyone present who had ever sent the wrong check to a payee.  A couple of people admitted that it had happened to them.

If you practice one-piece-flow, processing one unit at a time – in this case one bill—you practically eliminate that particular mistake.  You open one envelope, read the bill, write the check, put it in the envelope with the bill stub, seal the envelope and put a stamp on it.  If you wait to put stamps on the envelopes until all have been sealed and stacked, there is more of a chance of skipping an envelope and mailing it without a stamp.

Management Gets More Than It Deserves

In the factories that I visit, I find that management often gets more than it deserves from the production workers.  I remember a woman at a workbench, taking four parts from bins and using a machine to drive a rivet through all four to make a sub-assembly for a circuit breaker. She did this over-and-over, but her rhythm would often be broken because one of the parts had the hole for the rivet off location and therefore would not go together easily with the other three.  She would struggle to make them go together, and sometimes succeed in forcing the rivet through all four parts.  Other times she would eventually set aside the defective component and reach for a replacement, which, all too often, would also be so far out of spec as to be unusable.