There are many DFSS tools and from that we will discussed some Popular tools.
Needs VS Requirements
- Stated by the customer.
- May not reflect the true needs.
- Subject to interpretation related mistakes.
- These are explicitly stated.
- Needs are something that the consumer actually wants.
- These are implicit requirements and needs to be understood.
- It is very important to understand the difference between needs and requirements.
- While capturing VOC, it is important to ensure that not just the stated requirements but the implicit needs are captured accurately.
- The affinity diagram was developed by Kawakita Jiro to help in discovering meaningful groups of ideas within a raw list. It was named after him as KJ diagram or KJ analysis.
- KJ diagram sorts out disparate items from multiple sources into few essential statements.
- KJ diagram or affinity diagram should be used by the Black Belt immediately after he collects the customer requirements.
- For example, one may have got late because of sleeping late at night, waking up late, getting the bus late, chatting with friends, or some guests arriving at home. With the help of KJ diagram, these can be sorted out under the headings: Sleeping habits, guests, meeting friends, etc.
Quality Function Deployment (QFD)
- QFD is a systematic approach for transitioning customer needs to design requirements.
- QFD shows the competitive strengths of a company’s product versus its competitors’ products in the same niche.
- QFD will also show the possible weaknesses in the product in terms of adhering to the customer’s need (In DMAIC and DFSS projects).
- QFD was first developed by Professors Shigero Mizuno and Yoji Akao.
- The first step in QFD is the understanding of VOC and KANO model.
QFD can be extended to House of Quality (HOQ) to get a better understanding of process and customer needs. They are covered in detail in the DMAIC approach and are also a part of the toolkit.
- Assesses levels of customer satisfaction by ranking them on three parameters:
- Basic needs (Unspoken requirements);
- Performance needs (Spoken expectations); and
- Delighters (Unspoken excitement attributes).
- Every product will have its own set of expectations from a customer. For example, if someone wishes to buy a car, he would expect windows, brakes, gears, and tires to be provided. These are basic needs’ features.
- Mileage: Performance needs or expectations. If the manufacturer, doesn’t give the quality, the customer gets dissatisfied. If he does, the customer gets satisfied.
- Car lock alarms: Exciting. This was not mentioned. If provided, the customer would be super-delighted. If not provided, he wouldn’t be dissatisfied.
- The basic requirements of a product must be met in order for the product to be successful.
- The performance requirements should be prioritized in the order of what the customer wants, and should be delivered in order to stay in competition.
- The exciting requirements should be factored into the product, as part of a breakthrough strategy and differentiate with other competitors.
Important: Requirements should be sought and customer needs should be determined proactively and not re-actively.