# A Response to the Video Skeptics

By Ron Pereira Updated on May 16th, 2017

It’s safe to say the kinds words, comments, and emails for my one piece flow video have far exceeded my expectations.

While most of the comments and feedback have been extremely positive there have been a few skeptics in the crowd.  For the record, I love skeptics!  Why?  They push me to be better and to think.  And thinking is good.

Well, as of this evening, my new friend Eric H., of the GrimReader blog, has laid down a mind blowingly excellent analysis of my every move in the video.  Eric, as they say, has some serious eagle eyes!

Hi Ron;

Seems there are skeptics about. So I, hard-headed person that I am, watched the entire video again with a spreadsheet (similar data posted to my better half’s website).

How do we account for the ~60 second difference in the two processes? (Which I contend is the wrong comparison, more below).

Average time to fold:
Batch: 9 s
Lean: 8 s

Average time to stuff:
Batch: 4 s
Lean: 3 s

Average time to seal:
Batch: 2 s
Lean: 1 s

Average time to stuff:
Batch: 1 s
Lean: 1 s

So, over 10 repetitions, the lean method got a total of 10+10+10=30 seconds of advantage from the shorter time to fold, stuff, and seal.

Could the shorter fold time be due to thinner paper used the second time? Or to the fact that you seem to get better as you go (you start with times of 9-10 s, but end with times of 7-8 s). The shorter stuff and seal times, though, are due to the fact that you are already holding the item from the previous step. You gain 1 second each time from not having to find and pick it up. That’s part of the point, so I contend that it’s unfair to count those against you as if they were a parlor trick of some sort.

Still need to account for 30 seconds, though.

You lose between 2 and 5 seconds every time you move the pile around between steps. Also, you have to manage the pile several times during a task, something you don’t have to do nearly as much with OPF. This also has a factory corollary: storing, moving, retrieving, and looking for WIP.

But those are the wrong numbers to compare. The real advantage, though, is the fact that you are knocking out a complete product roughly every 15 seconds with OPF. Every 15 seconds, the lean manufacturer fills another order. Every 15 seconds, he has the opportunity to inspect WIP and final product for defects.

Heck, let’s even spot the batch production method the 3 second difference (most of which is legitimate gain) so that they both average 18 seconds. The lean producer would be still be fulfilling another order every 18 seconds. The Batch producer doesn’t get any orders filled until 3:47. What if they were hours rather than seconds? With 40 hours in a week, that means that the lean producer is shipping twice a week while the batcher is shipping every 6 weeks. Do you like the idea of cash flowing in twice a week, or every 6 weeks?

For the sake of the skeptics, next time you do something like this, make sure you do the lean method first so that your task times improve more for the batch method. Heck, handicap yourself for the lean method; use one hand and your teeth or something. 18 seconds beats 3:47 like a rented mule.

Update: The Fashion-Incubator blog readers have also chimed in with some passionate feedback.  Check it out.

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1. #### Stan

March 24, 2008 - 9:18 pm

Thanks for sharing this Ron (and Eric). It further drives home the point of why OPF is superior to Batch production.

March 24, 2008 - 10:05 pm

Wow! I went to that fashion site and can’t believe some of the comments. There are some ladies with serious issues over there.

I always find it interesting when people cast stones, yet do nothing to back up their barking. The people complaining and calling you out should keep their mouths shut before trying it out themselves.

Was the video perfect? No. But it was damn good if you ask me. I loved it and have shared it with everyone at my work. They also love it.

3. #### Ron Pereira

March 24, 2008 - 10:22 pm

Thanks Stan and Michael.

Most of the comments on Fashion Incubator (a very cool blog and application of lean thinking by the way) were either positive or constructive.

Sure a few were, well a little nasty. But as my Mama taught me a long time ago, sticks and stones…

4. #### Chris

March 25, 2008 - 8:55 am

I used your video as a guide in some training last week. I set two people up and let them go through the process with five envelopes, then had them switch processes and go through it again. One piece flow won both times. My compliments, Ron, on a great demonstration!

5. #### Ron Pereira

March 25, 2008 - 9:33 am

I am glad to hear it helped you Chris. If you want, next time grab a digital camera and roll camera and I will post your video! All the best.

6. #### Kathleen

March 25, 2008 - 11:43 am

In defense of my readership and like I told Ron, his video brought home a few points. First, for many of my readers, lean has always been an abstract concept, one they could support in “theory”. Ron, in applying practical expression, removes the abstract and as such, hits a little too close to home? I have little doubt there’s some cognitive dissonance and resultant defensiveness going on too.

Again as I told Ron, being roundly criticized is BETTER than being roundly lauded. Lauded means it’s an abstraction. Go Ron. Preach to the choir. Rah rah. Criticism means you’ve hit home and they’ve thought about it (defensive posture). If one’s points were groundless, there’d be nothing one would attempt to refute.

The point is, you get them to start thinking. Then everything changes. And oh yeah, even I still have spirited discussions with Eric (my better half) and America’s 21st (TSS franchise) over what constitutes one piece flow (where does a sub assembly begin and end?) and sometime necessities of batching.

7. #### Ron Pereira

March 25, 2008 - 3:23 pm