How to Innovate – part three: the Subtraction technique

A supermarket without packaging materials, a vacuum cleaner without a bag, alcohol-free beer or tape that does not use glue. Once ridiculous ideas… and each one of them turned out to be hugely successful.

In this short blog series, I will share some of the most powerful thinking techniques to develop new products and services. In this second article: the Subtraction technique. 

How to use the Subtraction technique to generate innovative new product ideas:

Step 1. List the key components of your product or service

Write down every component you can think of.

Step 2. Pick one component and imagine eliminating it

Remove one key component of your product or service. If removing the whole component doesn’t work, you can also choose to remove one of the functions or features of this component. Don’t be too quick to consider removing a whole component impossible though, give it some serious consideration. In our experience, almost any component can be removed, regardless of how ‘essential’ it may seem initially.

In some situations, removing a function can be even more radical than removing the component altogether. Removing a key component (e.g. beds from a hotel) or ‘merely’ a function (e.g. the possibility to lie down and sleep in the hotel) might seem quite similar at first. However, these different subtractions can lead to wildly different situations. In a hotel without beds, sleeping can still be an option. For instance, you could replace the beds with hammocks, sleeping bags, couches or air mattresses. When you remove the possibility to lie down and sleep, however, you are forced to look at your hotel in a completely different light. You might imagine a hotel for people who need a quiet place to work without disruptions, a party hotel or a ‘dummy’ hotel to train hotel staff.

Step 3. Visualise the product or service without the key component you eliminated

Imagine what the new situation would look like. It might seem crazy, but take a moment to visualise it regardless.

Step 4. Identify potential benefits and value

Ask yourself; what would be the benefits of this new situation? Who would be interested in it? When would this be valuable? (Or: how can this help me solve my problem?)

A pub without alcohol, for instance, might be interesting for people who don’t drink and dislike spending their night between drunkards, for people who are trying to resist the temptation (recovering alcoholics) or for minors who are not yet allowed to buy alcohol.

Step 5. Try replacing the function

If you see value in removing a component, see if you can replace the function of this component. Try to find the replacement within reach. For instance, when reimagining an anaesthesia machine, engineers imagined what it would look like without the screen they all considered essential. It would be cheaper, lighter, more mobile and it would require less power. So removing the screen clearly could be beneficial. The engineers looked for ways to replace the function of the screen (seeing the vitals of the patient) and quickly realised that they could send the patient data directly to the main monitor that’s already present in the operating room.

Step 6. Turn your idea into a valuable new product or service

How can you realise the idea? Can you implement the changes directly? Or does the idea need some tinkering to make it feasible? If your idea isn’t feasible right away, can you refine the idea to make it more viable?

Some innovative examples of products that subtracted an ‘essential’ element:

An ATM without cash

A children’s book with no pictures

Tyres without air 

Systematic Inventive Thinking

The Subtraction Technique is one of the creative thinking techniques that form the basis of the innovation method called Systematic Inventive Thinking (SIT). For more on this powerful innovation method, I highly recommend the book ‘Inside the box‘ by Drew Boyd and Jacob Goldenberg. The content of this article is largely based on this book.