About Dan Markovitz
Dan Markovitz is the founder and president of TimeBack Management. Prior to founding his own firm, Mr. Markovitz held management positions at Sierra Designs, Adidas, CNET and Asics Tiger. Learn More...
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Leveling; smoothing out the flow; e.g., doing two performance evaluations a day for 3 weeks, rather than ten a day for three days -- and then needing to take a vacation because you're so burned out.
Overburdening people, process, or equipment; e.g., people working 100 hour weeks for months on end -- come to think of it, like most lawyers and accountants.
Uneveness or variability; e.g., leaving work at the normal time on Thursday, but having to stay at the office till midnight on Friday because the boss finally got around to giving you that project...at 4:30pm.
Waste; activities that your customer doesn't value and doesn't want to pay for; e.g., billing your customer for the really expensive 10am FedEx delivery because you didn't finish the document on time.
TIMEBACK BLOG 
Batching vs. One-Piece Flow
Posted February 25, 2008 @ 4:55 PM
If you've been reading this blog for awhile, you know that many of my ideas about efficient work come from lean manufacturing. This is the framework I use in thinking about how to reduce waste.
One of the ideals of lean manufacturing is single-piece flow: building one item at a time to precisely meet customer pull. In this scenario, there's no buildup of needless inventory, because everything is built to a specific customer's demand. (Chrysler offers a cautionary tale about the consequences of building a giant pile of unsold inventory.) This one-piece flow stands in stark contrast to "batch processing," in which orders are built up to a certain level before production starts, in order to reduce average production cost.
Knowledge workers like you, who spend their days handling text files, spreadsheets, and email, can't operate in this ideal world of single-piece flow. For one thing, their work is too complex. You've got multiple value streams flowing through you, with each stream flowing at a different rate. That makes it impossible to determine takt time (basically, the average pace of work, for you non-Lean folks).
More significantly, the volume, speed, and variability of customer demand makes it ludicrous to work on each item as it arrives in order to precisely meet customer pull. You'd have to switch tasks every two or three minutes. But paradoxically, this is precisely what you do. Everytime an email comes in, you check it. Everytime the phone rings, you answer it. Everytime a coworker has a question, you stop your work to answer her.
For your own sanity (and efficiency), there has to be some sort of batching of work. But how do you reconcile that with the ideal of single-piece flow and customer responsiveness?
The answer, I think, lies in viewing knowledge workers as monument machines (large, complex machines through which multiple value streams flow). These machines inevitably take a certain amount of time to set up. Batch production makes sense for these machines, where the time and cost of setup is amortized over the entire production run. (That's why simpler machines are better, whenever possible.)
You're like that, too. It takes you awhile to set up -- to "get into" an engineering problem, a spreadsheet, or a performance evaluation -- so it makes sense for you to work in batches. (If you've ever been interrupted in the middle of one of these tasks and lost focus, you know the effort required to get back into it.) These longer "production runs" will reduce the waste and inefficiency caused by switching between tasks too often.
Of course, this means that inventory will build up -- unanswered voice mails and emails in particular -- so the flow of the value stream won't be perfectly smooth. But I believe that the waste of waiting borne by the downstream person (or the ultimate customer) is less than the waste caused by you switching between tasks several hundred times per day. The best you can do is to minimize the waste of waiting by batching your email and voice mail -- dealing with those inputs regularly, two to four times per day, for example. And in all likelihood, this kind of methodical approach to handling your paper and electronic inboxes will result in fewer lost or unacted-upon tasks.
So take a few minutes and look at your work as a value stream. Apply the same critical thinking to your workflow as you would to a physical production line. And see if you can't justify intelligent and mindful batching, instead of the mindless urge for one-piece flow.
One of your best posts, Dan.
Submitted by Matthew Cornell (not verified) on Tue, 2008-05-27 13:08.
One of your best posts, Dan. Your tie-in of lean + personal workflow is your #1 contribution opportunity in the field. IMHO.
Human Productivity
Submitted by Keith Bossey (not verified) on Fri, 2008-03-21 23:16.
Excellent description of the barriers to knowledge worker productivity. We work with lean manufacturers to enhance the relationship of the worker to the process (ergonomics), but poor workstation design happens in the office too. Bad design doesn't have to lead to injuries to make a difference. Bad ergonomics in the office makes it real easy to want to get up from your desk, making it hard to "get into" your work.
Reply to 4HWW
Submitted by Dan Markovitz (not verified) on Sat, 2008-03-01 04:32.
Tim,
Thanks for the comment. I see the similarity with the 80/20 Principle and 4HWW as well, and see all of these approaches as simply a different way of expressing the same ideas - much as there are thousands of love poems, and you never know which will hit you.
4HWW
Submitted by Tim Bowen (not verified) on Thu, 2008-02-28 02:59.
It makes a lot of sense to bring the ideas from lean manufacturing into personal time management.
I certainly agree with your batching conclusion. This matches well with the way I've found myself to be most efficient and to those theories made popular by the 80/20 Principle and The 4-Hour Workweek.
Batching vs. One-Piece Flow
Dan i am reading you from ages and i was thinking about from where you make the idea or get the frameline, nice way of thinking i like the stuff on your posts.