Pull System

C-3P0 Timebox

Standby Autograph with C-3POMy family and I recently went to Walt Disney World’s Magic Kingdom and Hollywood Studios. My wife was extra excited because it was going to be "Star Wars" weekend at Hollywood Studios while we were there. Imagine parades filled with Star Wars characters, Storm Troopers and Clone Troopers everywhere...and the force being with us (or maybe not). My wife was very excited when she found out she had a chance to get a picture taken with and get an autograph from Anthony Daniels of C-3PO fame. This is how it was to go down. When the park opened, a predefined amount of tickets would be given to those people standing in a line. Once those tickets were gone, there were 30 remaining "standby" tickets. There would be two autograph sessions, lasting one hour each. IF Mr. Daniels got through the "guaranteed" group of ticket holders in less than one hour, he would then start to greet the standby ticket holders in the order in which they arrived that morning. We were standby ticket holders #19, #20, and #21 (out of 30). Everyone was required to stand outside in the sun until their ticket number was called. They were then allowed into an air conditioned building to meet C-3PO. When they were done, the "beaming" fan exited the building.

Well, the morning session (in close to 90 degree heat) came and went. The first 10 or so standby ticket holders did get in. We were told to return in the afternoon. Upon returning in the afternoon, the guaranteed group came and went and as we watched the clock tick closer and closer to the one hour mark, they accepted standby after standby. We had convinced ourselves that certainly Mr. Daniels would understand that there were only a few people left in line and would stay the extra 5-10 minutes it would take to greet us and sign a quick autograph. Unfortunately, after #17, a representative walked outside and told us that Mr. Daniels had to leave for another scheduled engagement.

At first, I was pretty pissed. Seriously? He couldn't accept just a few more people and get through 100% off ALL of the people standing in line? No, later I thought about it. He had a timebox. He had exactly two one-hour sessions. He was going to get through as many autographs as he could but he still had to leave after one hour, regardless. He agreed to sign a specific amount of autographs and he met that commitment... and he exceeded it.

Have you had that situation happen to you as either a ScrumMaster, Project Manager, or Stakeholder? As a stakeholder you feel ripped off because someone else got something delivered and you didn't. As a ScrumMaster, you have to allow the team to commit to do the work. You can't force work upon them. As a Project Manager, you have to explain to everyone that if you let the time constraint slip, you would be asked to do that every time there was a commitment. You've heard it before. Please, just one more thing. Please, just one more day.

Mr. Daniels, you did the right thing. You kept your commitment. If that gig as protocol droid doesn't work out for you, I'd hire you.

Theme Park Pull System

Roller Coaster LineIf you've been to a theme park like Disney World's Magic Kingdom or Hollywood Studios, you will quickly notice the lines.  Depending on the time of year (or day) the line to a ride or attraction could be anywhere from nonexistent to 90+ minutes long.  As you approach an entrance, you'll see a line marked on the grounds and a sign that reads "N minutes from this point". You want the sign to read 5 minutes.  That's the time it takes, with no wait line, to get to the actual attraction.  What you don't see from the line on the ground is the maze of lines snaking their way through the building.  If the volume of people is low, everything except the direct line to the attraction is roped off.  The more the people, the more "side" lines are open.  The line outside the attractions are deceasing.  The real delays start after you cross that line marked on the ground and are committed. I noticed that attractions usually lasted less than 5 minutes and people were divided into groups, just prior to onboarding some kind of transportation.  The transportation ran at a consistent rate of speed.  All these factors included, Disney World has to know the maximum throughput of a ride, before the line starts to back up. Why do you ask?  Well, to keep the customer happy by keeping them moving, of course.

When I saw all of this happening, I thought it was an excellent example of a pull system.  We went on a ride called "Star Tours".  The vehicle capacity was 40 people and the ride duration was 4:30 minutes.  We noticed the sign said 90 minutes from this point.  Can you imagine doing that with a 5-year-old?

Star Tours Capacity=40 people per load Lead Time=90:00 minutes Actual Duration=4:30 minutes

So, what does Disney do to help resolve the issue?  They call it the Fast Pass.  Yes, the golden ticket.  When you see the line at its worst, go up to a kiosk and get a Fast Pass.  It will tell you to return to the ride at a designated time.  In exchange for doing that, it will allow you to go to the head of the line, when that time comes.  I am assuming they are having you return at a predicted time of day in which the line will be shorter.  Regardless, it eliminated the bottleneck for us.  Whenever we saw a hellish line, we got a Fast Pass and came back later in the day.

To prevent the Fast Pass people from completely stopping the line, it appeared a certain percentage of seats per load were allocated for Fast Pass ticket holders.

I think this Fast Pass option may also work with non-theme park customers.  Let's say you are working on an application development project.  After you have an optimum cycle time, if you reserve a little capacity, you could potentially negotiate with a stakeholder to postpone an activity to a date or time in which you know the workload will be less.  I'm not saying you are postponing adding the work to your backlog.  It's still there.  But, you could agree to make it a lower priority until more of the backlog gets completed.  This could keep the rest of the work moving at an optimum pace and keep the customer happy.

Drawing by Pictofigo

Valentine's Day Pull System

Nothing is quite as romantic as sitting with your husband or wife, sharing a dinner of fondue.  Nothing, that is, unless you’re sitting with me.  I’m not a big fondue guy.  This is sad because my wife loves it.  She enjoys the whole process.  To counter that, I like my food to be given to me, already prepared.  I enjoy the results! So, leave it to me to point at the fondue pot half way through dinner and yell “Fondue is a pull system!  Fondue is a pull system!”

What is a pull system you ask?  Perhaps you’ve heard of Drum-Buffer-Rope or Kanban?

Businessdictionary.com defines it as a Manufacturing system in which production is based on actual demand, and where information flows from market to management in a direction opposite to that in traditional (push) systems.

The idea behind a pull system is to keep a smooth production flow.  For the sake of argument, let’s say N is a volume of work output.  It can be trouble-ticket call volume, software development, or hardware manufacturing.  Any of these work in the example.  If you and your team can consistently deliver quality N in a month, and keep a good work-life balance, you should know that a C-Level executive asking you to deliver N+10 is going to create bottlenecks in your process flow.  Your overall delivery velocity is going to slow and your team is going to work longer hours trying to deliver N+10.  This increase is unsustainable unless something changes.  You need to get back to N, either by cutting back the work, expanding the amount of people or things to complete the work, or find some efficiencies.

You limited your work in progress (WIP) for a reason!  If more is going into your process than is coming out, you’re going to accumulate a backlog.  For every unit exiting your process, you should have another unit ready to enter it.

For fondue, you limit your work in progress by the amount of long-stemmed forks you have to put into the pot (caquelon).  Before you start, you cut up all of your fruits, vegetables, meats...whatever you plan to dip.  That’s your product backlog.  You then begin dipping whatever you have, X at a time.  We had 3 forks each.  When the food is done, you take it off the fork, add another piece of food, and back into the pot it goes.  You can’t eat anything until it’s done with the process.

Am I a romantic buzz kill or what!?

Image: Recipe Tips