Comments on: Multi-Tasking Leads to Lower Productivity

By: Dave Crenshaw

Dave Crenshaw — Mon, 23 May 2011 06:01:16 +0000

Multitasking has become something of a heroic word in our vocabulary. Many executives pride themselves on their ability to “multitask”. Recent job descriptions that I have seen even ask that potential employees have the ability to multitask. A current national commercial sings the praises of multitasking. However, multitasking, as most people understand it, is deceptively counter-productive. Multitasking is tremendously costly and hurts us every time we attempt to engage in it.
To learn more about the effects of multitasking, take my free exercise at http://www.davecrenshaw.com/exercise

By: robert

robert — Wed, 13 Apr 2011 03:15:28 +0000

In reply to robert. Sorry.

By: robert

robert — Wed, 13 Apr 2011 03:10:59 +0000

In reply to jack.

I was going to say the same thing as jack above. From a mathematical standpoint, that equation doesn’t make sense.

If you increase WIP and TP = WIP/CT, then you increase TP as well.

If you define WIP as, WIP = CT x TP, then you have CT (seconds) x throughput (units/time). This gives you [units] as an output, which works for work in progress. I think the thing that makes this analysis not work, is that when you increase the work in progress, you also increase the cycle time because your attention is divided and tasks take you longer than if you hadn’t split them up.

Your throughput will change depending on how efficiently you multitask. If you increase the the WIP, and keep CT the same, you increase TP. Likewise, if you keep WIP the same, and reduce CT, you will increase TP. All multitasking articles and research I’ve read says that you actually increase CT more relative to WIP increase and hence, decrease total TP.

I suggest that someone study multitasking efficiency, especially of those supposed supertaskers out there. One article I’ve just read says that 1 out of 40 people are supertaskers (2.5%). There is current research being done to see whether these people can perform more complex tasks than just driving.

By: lucky

lucky — Mon, 09 Mar 2009 14:09:56 +0000

what you have not considered is that certain human brains are desired primarily for multitasking/multithreaded concentration. adhd if the clinical term we typically use for these sorts of people. so to design a system around a common human weakness is only going to reduce the productivity of people who are stronger at multi tasking than singletasking.

it’s something you should at least consider.

By: psabilla

psabilla — Tue, 04 Dec 2007 18:56:34 +0000

@Jack,

You’re intuition is spot-on. These are equivalent, in fact:

(WIP=CTÃ—TP) == (TP=WIP/CT)

The bok “Factory Physics” explains this much, much better than I have.

Thanks for stopping by.

By: jack

jack — Tue, 04 Dec 2007 18:43:39 +0000

Your math doesn’t work at all. You’re making a great point, but this equation just doesn’t work:
Throughput = (WIP / CT)
since the math means that increasing WIP would *increase* throughput given a constant cycle time. Maybe you meant CT / WIP , where CT is time to complete 1 work unit and WIP is in work units?

The rest of the article implies that the concepts of WIP and CT are interrelated; taking that in to account would definitely help the explanation.

By: Gary Patton

Gary Patton — Tue, 10 Jul 2007 17:21:21 +0000

I currently own the domain name multitaskingsucks.com

I am just getting started but wondered if you would be interested in advertising on my new site.

Please let me know if you would have any interest.

Gary Patton

By: james

james — Wed, 04 Apr 2007 15:14:39 +0000

Good stuff! We see this everywhere including in personal time. How many times have you held a conversation with someone who is simultaneously working on their e-mail? The end result is that neither task gets completed as well as it should.

james

By: robert thompson

robert thompson — Tue, 03 Apr 2007 08:47:45 +0000

You say: multi-tasking actually leads to lower productivity and lower morale. I made this exact point on one for my blogs here: http://tinyurl.com/28j94q.

The main leanring point is what Deming called Consistency of Purpose – focus until the task in had is complete. Here is a great example of a lack of this concept in action (http://pages.citebite.com/p1f4c8e1b9bxu):

I’ve never seen a company with the lack of consistency of purpose as Ford, Mulally told reporters. He stirred up buzz by visiting Toyota, seeking not so much to do business with the company as to learn something more about how the car industry works. “Consistency of purpose” might be the most cogent three-word explanation of what’s behind Toyota’s success. From the top execs down to the guys sweeping factory floors, everyone there knows the mission is to serve its customers.

Rob