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Subtraction – A Tool of Systematic Inventive Thinking (SIT) Method

This article is based on the book "Inside the Box" by Jacob Goldenberg and Drew Boyd, describing the method developed by SIT.

Three Examples of Subtraction

First Example

A large metal-works company produces individualized and unique products for clients, with each product different from the next. Each product is produced almost completely by one employee, who signs off on it. If a client complains, the producing employee investigates the complaint and writes a report. The employee then fixes the product, and resends it to the client.

Employees are fully responsible for the quality of products, and the production floor has no quality assurance supervisors. There's no need for them. But that isn’t enough, production is planned and monitored by a PP&C system which schedules times of production and shipment exactly.

This way, the need for excess managers also decreases. Each employee is responsible not just for quality but also for meeting deadlines. The production floor has about 150 production workers and only one manager. When I was there the manager was absent and work took place with a very high level of personal responsibility.

This work method subtracted quality assurance supervisors and managers and added discipline and responsibility for every employee – the necessary tools for creating motivation. Turn-over rates and absences are very low.

Subtraction contributes not only savings on quality assurance supervisors and managers, but also creating disciplined and motivated employees, with low absences and turn-over rates.

Second Example

At the same company, products had been sent to a logistic warehouse before being shipped to clients. Since each product has a different address, managing the warehouse was problematic, and in order to make it easier – the company purchased a much larger space. Shortly after the purchase the company received an offer they couldn’t refuse – rent the space to another company for a good price. Temptation was high, but their work method required a warehouse.

Necessity gave birth to a creative solution which needed a different organization of the supply chain. They started working without a logistic warehouse. Products are sent directly from the production floor to the client.

The company needed an efficient PP&C system to schedule production, supply clients and manage a geographically efficient shipment system. With creative thinking and dedicated and motivated employees – they succeed.

Third Example

My good friend Itamar Cohen developed a system called Nemlock, to open doors using a smartphone. With no need for a key, a chip, or any other accessory. The system is remotely managed on the assumption that now-days, when every child or adult have a smartphone, it's possible to allow anyone to enter in different hours, with permanent or temporary access. Now think of a youth club, a community center, local gym, or your own home – instead of handing out keys and having to keep track of them – everything is managed electronically, and even when the kids get home from school they don’t need to carry a key.

The subtraction used by Itamar isn’t only of a key or other accessory whose role in opening the door is eliminated. The essence is simple and smart management of the right to open the lock and enter a home, club, center, pool, etc. Instead of the subtracted key, the system utilizes an accessory most of us already have: a smartphone. I believe anyone managing a community center or using one often appreciates Nemlock's use.

The Common Denominator

The three examples described above show innovative creative thinking using, among other things, subtraction of an element which was inherent to the system (quality assurance supervisors, a logistic warehouse, and middle managers in the first two examples; key or chip in the third). As far as I know the subtraction in these examples was a result of innovative creative thinking, and not a cause of such thinking.

I believe you know further examples. Like fast-food restaurants without waiters, but rater with self-service instead.

SIT – Systematic Inventive Thinking

SIT is an Israeli based company which developed the subtraction technique as a tool for creating innovative thinking, when there's a block because of paradigms and fixation. This technique, along with others developed by the company, is described in the book "Inside the Box" by Jacob Goldenberg and Drew Boyd.

The Subtraction Technique – Initial Explanation and Example

This explanation and example are taken from the book's second chapter.

Johnson & Johnson were developing a new anesthesia machine. The development team thought the prototype had reached the last stages before production. But Mike Gustafson, then head of the anesthesiology department, wasn’t pleased. During 2002 Amnon Levav, CEO of SIT, was invited to conduct a one-day workshop with the development team, which included engineers and marketing people.

The team was locked into the thought the prototype was nearing the end-of-development stage, and was fixated on a standard product structure. They didn’t believe in the guest coming to waste their time, and the room was adversarial.

Amnon asked them to list the prototype's main components: screen, keyboard, casing, central processing unit and power supply. Due to Ministry of Health guidelines there was also a backup battery in case of power outages.

He divided the team into pairs. Each pair got responsibility for one component, and was asked to imagine how the machine would look without that component. Try to imagine the resistance and sense of time-wasting Amnon was met with at the moment.

The first pair presented the benefit of subtracting the backup battery. Without it the machine will be lighter, cheaper, and simpler. One of the engineers said that if they could subtract the backup battery the whole project will be much simpler.

Now, it there's a benefit to subtracting the battery, then it, or its role, need to be replaced by a component from the "closed world". The closed world is defined as an imaginary space in place and time where everything (people, objects) is at our disposal. That is, a component that is already existing. That is one of the principles of subtraction. The place of the subtracted element can be filled only by an element that already exists in the system's "closed world".

One of the engineers suggested connecting the machine to another machine's backup battery. In the same way, the screen was also examined. Subtracting this component will also result in a lighter, cheaper and simpler machine which will need less power. After examining the screen, the team decided to transfer the information from the anesthesia machine to the operating room's main monitor.

In this case, in addition to subtracting the screen, a second benefit resulted – the surgeon will need to look only at one screen, instead of two.

Using Subtraction. 5 Basic Steps:

  1. Write a list of all the components of the product or service.
  2. Choose one essential component and imagine what would happen if it were removed.
    Note: it's best to choose a component that isn’t the most or least essential – one in the middle.
    There are two ways to conduct this thought experiment:
    1. Full subtraction (the entire component is removed).
    2. Partial subtraction – remove or minimize one of the component's characteristics or roles.
  3. Imagine the final product (even if it seems strange).
  4. Ask yourself – what are the potential benefits, markets, or values? Who will be interested in the new service or product, and what will its value be? If you're trying to solve a specific problem, how will the new product or service help deal with this challenge? Then think how you can replace the subtracted component with another one from within the "closed world", and what are the benefits, markets, and values after the change.
  5. If you've decided the new product or service has value, ask yourself, is it applicable, can it be produced or implemented? Why? Can you adjust your design to make it (more) possible?

Common Obstacles When Using Subtraction

Goldenberg and Boyd list five common obstacles:

  • Don’t subtract only bad components. Such a subtraction meant to improve performance isn’t employing the subtraction technique, but is rather a slight improvement of characteristics.
  • Try to subtract essential components. See how in the above examples the subtracted components had previously been thought of as essential.
  • Don’t immediately replace the subtracted component. Our structural fixation, leading us to try and keep the product looking the same, might push us to look for an immediate replacement. Use innovative and creative thinking first. On the other hand, when subtracting an essential component you might be damaging the product. Be aware of both possibilities.
  • Don’t give in to cognitive dissonance. That is, don’t try to change the way you think of the product's purpose following subtraction. Stay true to the product's purpose.
  • Avoid simple downgrading. Subtraction isn’t the same as downgrading – eliminating characteristics of lowering quality and selling for a lower price. Subtraction will give you a new benefit after eliminating or changing a component.

Tivall's Schnitzel

According to online publications, Tivall's schnitzel was developed as a vegetarian substitute for regular schnitzels after a consumer survey found it to be the most popular meat product in Israel. This is another good example for subtracting an essential component (meat from schnitzel).

Like my first examples, in this case subtraction was a result of innovative thinking, and not of the SIT method. Tivall's development took place before SIT was founded.

Summary and Recommendation

The above article is part of a category dealing with R&D, or with developing new products or services. Developing new products is a company's lifeblood. A company that stops investing in development and innovation is starting the countdown towards its end.

The subtraction technique is one of the tools developed by SIT in order to create innovative thinking. Of course there are other ways and creative people, but our "natural" fixation threatens to thwart any attempt at innovation. The fixation which preserves the known and familiar, makes it difficult to create something new.

In the above article I presented examples of innovative thinking which created subtraction (like Nemlock, or Tivall's schnitzel) and an example of using the subtraction technique to create innovative thinking (Johnson & Johnson's anesthesia machine).

If you don’t invest in development in a structured and institutional way, I recommend you budget for a development department, and use different tools and outside people (who are not part of your day-to-day and so are less fixated) in order to work at constant innovation and development.

If you are interested in my professional help, personally or for your company, the best way to contact me is to send a request through the Get in Touch form here.

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