Is Batching Always Bad?

You might be shocked, Ron, that as a “Lean Blogger” (not a “Blogging Blogger”) I often batch up my writing and then release posts over time in a “level loaded fashion.”

There are times when I “get on a roll” writing and I do multiple posts in a sitting. Maybe it’s “overproduction” but the feedback from my readers is that it’s better to have one post a day instead of 3 on one day and nothing for the next 2 days.

I don’t see this as any huge problem, as most of what I blog about isn’t super timely. I don’t think there’s any benefit, in the case of my blog, to any “single piece flow” dogma.

Now, in a hospital lab I’ve worked with…. single piece flow *is* clearly superior for the processing of patient specimens that arrive in the lab. We’re shifting people from batching work to single-piece flow, which is reducing cycle time and helping improve quality. So don’t think I’m in love with batching. It depends on the situation and the value/waste equation.

Now, in a workplace setting, again, some batching might be necessary depending on demand and capacity. When things are really busy in a lab, you can’t always run a centrifuge with just 2 specimens at a time…. you have to allow things to batch up somewhat or otherwise you won’t have enough capacity to get all of the work done. But during slow times, you might do just 2 at a time so you’re not waiting too long to let a larger batch accumulate. There is often a tradeoff between batch size and capacity. You have to first meet capacity needs, but then with the smallest batch size possible.

I’m not making excuses for batching, but I’ve found you sometimes have to be practical about it, not dogmatic.

Remember, it’s not single-piece flow for it’s own sake. It’s single piece flow to provide value to the customer as quickly as possible. By focusing on one task through to it’s conclusion you serve that goal. I suppose somebody unfamiliar with lean terminology might call that batching, but I’m not sure I would.
Reading and writing email a few times per day means fewer interruptions to the flow of other tasks. That’s certainly lean. The unit size is not each individual email message, it is the daily task of handling all email.
I suppose the question is, who is your most important customer, the emailer, or the customer for all the other tasks in your day.
Your quote also says that he gets down to 0 emails in his inbox. That means he’s not keeping inventory day to day. I wish I could say that.

-Andy

In transportation, it sometimes makes sense to batch instead of sending less-than-truckload, especially with gas prices the way they are. In this energy-challenging environment, I’m sure Toyota is doing less of the “small batches, frequent trips” strategy in their supply parts business (I was on that side of the business) and opting for “a little bit bigger batches, but less frequent trips”. In either case, Toyota still does batches — the question is about “how big should the batch be?” The goal should be a batch-size of 1, but if not, then you increment from there.

I disagree. I’ve tried to write emails, articles and books via batch and queue of ideas … it doesn’t work for me. I end up re-reading or re-writing the same things over and over in different parts of the article because I forget what I’ve read or written earlier. It’s very inefficient. It’s always best to develop the outline (equivalent of process) then populate each section in one sitting (equivalent of single piece flow). Reviewing that work after it’s done is like having an inspection point beyond the production of the part.

Regarding emails, sorting out the different types of subjects is like sorting materials to different production lines. Batch and queue under this context would be like sorting out all the emails of a certain subject then compiling and pasting in one email to respond to all the emails… which no one does because we naturally know it’s inefficient.

KN

I think it depends on from whose point of view you are viewing a given operation. In case of an email, if the point of view is from a person waiting for my reply, I guess he would prefer me to apply single pice flow. Whereas if it is just informational mail (where I am the customer), then I may be more efficient with batch and queue.

Having said that, in any batch and queue scenario, there is always WIP. Its best to keep this WIP optimal. For example, pile up of too many informational mails for days/weeks may not be a good idea. Daily or weekly clearance of informational mails in small batches helps.

My takeway – Batch/Queue or Single piece Flow? Batching looks more efficient for the task executor. However, task customer will always perfer single piece flow. One has to strike a balance between these two bi-polar needs