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by Russel Watkins

If you're human, time matters because it’s so central to our lives. If you're a human working in lean manufacturing, time really matters because it's also deeply embedded in our day jobs. There is a philosophical argument that views time as an artificial construct created to denote the interval between events. This is a fair point and hard to argue but time also serves other purposes.

Let’s take a look at these other purposes for time, in all of their glory and darkness. In practical terms there’s a very positive side to our lean fascination with time but there is a darker side - a circle we have yet to square. More on that later.

The light – why time is a positive part of lean thinking

Why is time so central to our lean thinking? A lot of us accept that lean is a socio-technical system, a heady combination of a million variables brought together within a technical environment. At its heart there exists a social system of people and tribes at work that have to bring the 4Ms together to make something useful and valuable to sell.

At the most fundamental level we consider time in terms of Cycle time, Takt time and Lead-time to work out our ability to meet customer demand and stay competitive, doing it within a shorter lead time as possible. Time is also at the heart of industrial engineering and, if we can avoid the Taylorist traps, we need time because it gives us a measurement means - to gauge the “after” in relation to “before” so that we can see if our improvement efforts have worked. It’s a key part, amongst other things, of the of the PDCA cycle.

Taichi Ohno, in formulating the essence of TPS, was a big fan of time compression. Numerous sources quote him summarising our aim as something like “all we're trying to do is compress the timeline between paying and getting paid”. Indeed, the whole impetus behind Value Stream Mapping (VSM) is based on the presupposition that, to compress the lead-time we take away all the things that make our factories unstable, we flow product better, and pull where we have to, to a levelled drum beat. This, in simple terms, lets us whip material through a factory faster, stops inventory sitting around, and gives us a shot at the holy grail - to get paid by our customers before we have to pay our suppliers (not forgetting the advantages of offering a shorter lead-time to customers). This time compression can be applied to any of the production and non-production value streams in the business to generate competitive advantage. Notably, New Product Introduction brings innovative ideas to market faster, but as discussed below, herein lies the dark side of the force.

One of my favourite definitions of lean came from Art Byrne when he described lean as a “time based growth strategy”. There's a lot to admire in this short collection of words in describing lean as a strategy to grow the company and the capability of its people through time compression. A useful definition because it focuses us on blocks and detours to the flow of value.

So, in a technical sense these are any number of reasons why time is so central to us in lean – positive reasons. Let’s build on this with the socio bit of the socio-technical manufacturing view. My Toyota sensei Toshiyuki Muraoka worked for 34 years at the Kamigo plant under Ohno-san as he developed, amongst other things, the Kanban system. One of Muraoka-san’s favourite phrases was:

“Time is the shadow of motion”

It’s a beautiful phrase that makes us think about waste (muda) differently. If you want to reduce cycle time for example - counterintuitively - don't try to go faster. Instead, analyse and improve the motions that cast the shadow of time. Reduce the motion -> reduce the shadow -> reduce the time.

This example is helpful as it takes us into a more human consideration, a respect for people aspect. We can deepen this respect for people aspect of time with another Muraoka-ism reflecting the Toyota world view:

“Time is the only resource we share equally”

The beauty of this phrase is surpassed only by its usefulness when a cartoonist with the skill of @sketchplanations brings it to life in the following “Cost of being late” visual:

At the risk of disappearing into a philosophical rabbit hole, this echoes the Chinese adage that “life unfolds on a great sheet called time, and once finished it is gone forever”. The practical takeaway – being late, dragging out meetings, calling unnecessary meetings as a leader – is fundamentally disrespectful to people as you’re, literally, stealing their existence.

Returning to the factory floor, we can bring the socio and technical sides together quite nicely with gemba sensitivity - developing the ability of our people to see, smell, hear and sense things going wrong in a factory. When you start on the gemba, as a novice, you hope to find problems and find them quickly. As your knowledge and skill gets deeper, and your calibration to your environment gets better, your understanding of which inputs cause certain outputs improves. In a nutshell, you start to look for abnormalities rather than problems, things trending the wrong way or things that, if left as they are, will cause a problem. As your skill deepens again you consider, grasp, communicate, and manage change points (Henkaten). A lot of accidents and defects happen after change points. This highest expression of gemba sensitivity skill is a form of time travelling, the anticipation of possible problems. Time is indeed a powerful force in lean!

The shade – why time is a double-edged sword

It helps to look at the difficulties arising from our time fascination in lean from a real world perspective. The common theme in this next section is the relentless coupling of consumption and production, a coupling inherent to the success of our two case studies - Zara and Amazon. Let’s start with Zara.

On the face of it Zara should be a lean poster boy, the Spanish business is 50 years old and incredibly successful. They engage in a lot of lean style practices like JIT, Kanban, and kaizen, engineering some tremendous lead-time compression results. In fact, the phrase “fast fashion” may have originated with Zara.

Zara comes up with new design releases every two weeks, releasing 3 times as many new garments per year as their competitors who design release every three to four months. For Zara there aren’t 4 seasonal collections, there are 20+. They've compressed their entire lead time, both on the non-production and production sides, from concept to design freeze and then from design freeze to mass production (including the supply base)

In a lean sense this looks like ‘high fiving’ territory, but fast fashion has its downside. Zara has been accused of greenwashing, exploitation of cheap labour sources, and environmental distraction. Yes, they measure their concept-to-material in days (as opposed to months for the competition) but, for every new design released into the wild, we find increased microplastics, water and wastewater usage and treatment.

Perhaps the most damaging aspect, long term, is the mindset it embeds – clothes are consumable items, no longer cherished and worn for long periods. In summary, from a purely technical lean sense we celebrate Zara’s innovation and drive to compress timelines. In a broader sense we shift uneasily in our seats thinking of the overuse of scarce natural resources. The “tragedy of the commons” writ large and sanctioned by, ahem, all of us.

The second example, Amazon, looks at a slightly different downside of our fixation with time. Again, there's a lot to admire about Amazon’s growth and success. There are concerns though and, in respect to time, it's around their ability to compress customer fulfilment and replenishment lead-times. There is, though, an unintended lead-time compression consequence we've got to face.

As a lean thinker I'm all over lead-time compression for the get-paid-before-you-pay potential, the flexibility benefits in satisfying changing or late customer schedules, and the relentless focus it gives to eliminate muda, and reduce muri and mura.

But the unintended consequence in the Amazon model is that we've (all of us) let them blind us an important thing. In offering shorter and shorter delivery expectations, shipped from cleverly stocked warehouses, we're forgetting that there's a natural lead-time to things. If it's manufactured - there's a lead-time and a chain of people putting in effort to get that product to us.

Next day delivery as a norm makes us forget this, makes us forget to have "Kansha". Kansha refers to deep gratitude and is often expressed around a Japanese dinner table in the word “itadakimasu”. It’s the act of giving thanks for the people who grew the food, harvested it, packaged it, transported it to the supermarket and cooked it.

In manufacturing - it keeps us humble in the factory in remembering that there is a long supply chain of effort to any product. We’re more likely, collectively, to respect the things we produce if we understand that there's a lead-time hidden behind the 1-day-delivery.

In the real world few enough people care about manufacturing as it is, without helping them to forget that manufacturing matters.

So, lead-time compression? - yes- I'm in, always have been.

Forgetting that there's a lead-time? - I'm out.

Almost everything we touch or use today has been manufactured and the challenge is to pursue lead-time compression whilst respecting the creation process and the efforts of everyone within it. It's not Amazon's problem, it's ours. How do we strike this balance?

Striking the balance?

I thought long and hard about what the call-to-action for this article should be. The first point is that as lean enthusiasts we should “advertise” lead-time compression successes in a more rounded way – perhaps even choose more balanced exemplars.

The second point goes right to the heart of a hoshin goal set by Mitsubishi a couple of years ago. They asked themselves

“What if there were no parked cars in the world”

This is fascinating, and a little scary, as it takes us into the “sharing” aspect of CASE (Connected -Autonomous – Sharing - Electrified) and the harsh facts of current sharing. Each of us in our streets and neighbourhoods has a power drill, each of us only use it for 15-20 minutes in its entire life. Logically, we should be sharing one power drill between several of us – but that’s a purely rational argument (availability to one side) and there are social challenges to sharing household appliances to be sure. In a similar vein, you can't argue with Mitsubishi questioning, in an apparent turkeys-voting-for-Christmas way, why there so many parked cars in the world?

If we want to preserve our planet by better coupling consumption and production, via sharing and other means, in the short and medium term we may decimate industries and put people out of work. Imagine we did get to the point where there are significantly fewer parked cars in the world, that's fewer automotive factories and supply chains, producing fewer cars. That's fewer jobs for people to earn a living and put food on their table. Now extrapolate this across all of our physical consumption patterns and consider the potential for widening inequality and social unrest.

So my call to action is this: whilst we rightly celebrate the companies that do a stellar job on lead-time compression, let's take a look in the mirror as consumers and lean people, and ask ourselves:

What price are we paying if we drive lead-time compression purely to get people to buy more of the same?


Russell Watkins is the Co-founder of Sempai®, assisting organisations serious about improving the performance of their business. He has held Operations, Materials and Lean positions within the Automotive, Aerospace and Construction Equipment sectors. Russell’s Lean transformation work has taken him to shopfloors and boardrooms in the UK, Europe, the US, China, India, Japan and South America. He is also leading a digital start-up around lean skills, whilst helping manufacturers with his keen eye for identifying and supporting Industry 4.0 opportunities. Russell is the author of “Adventures in Leanland” a speaker and awards judge. Russell loves factories, they are the ambient soundtrack to his life. Training & coaching a thousand+ people creates a lot of stories to share

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