This illustrates the degree to which the requirements (whats) are significant to Toyota customers. The rating scales of 1-3-5 have been used to measure and rank the importance of those customer requirements; 1 represents slightly important; 2 represents important; 3 represents a very important requirement. Take, for example, the availability of spare parts. Customers have identified and ranked this as 5 in terms of significance, which represent a very important requirement. Not fulfilling this requirement can lead to customers’ dissatisfaction and frequently losing them. Another example is cars with zero defect, customers have also prioritised this requirement and given it a rank of 5, which means it is very important to them.
- Interrelation matrix
The purpose of interrelated matrix is to measure the perceived relationships between customer requirements and operating requirements. In this house of quality, the relationships have been portrayed by symbols indicating a strong relationship, a medium relationship, and a small relationship. The symbols in turn are assigned a 9-3-1 index. When no relationship is evident between a pair (process & requirement), no value has been assigned. For instance, the relationship between the stylish design requirement and new car styling process is seen to be strong; therefore, the symbol which indicates to a strong relationship has been assigned to them. Likewise is the relationship between the zero defect requirement and new car testing and evaluation.
- Importance weighting
Importance is a result of multiplying the customer importance value of each requirement by the value of the relationship between every requirement and process. The result is then summed and place into the related importance weighting part. The highest weighted process appeared to be transformation process.
- Target Values
Each process has a target value which any company aims to achieve and Toyota is not an exception. The target value of each process of Toyota Company has been established and entered in the relevant section. Take, for example, the new product development process of Toyota. The target value of this process is to develop and create a new car model every four years. Another example is the spare parts inventory process, the target of this process is to ensure zero shortage of any necessary spare parts in the warehouse.
- Technical Evaluation