Organisations use development methods when developing a product or a service, to help them deliver the product/service efficiently and also to help them keep cost of production to a minimum. There are quite a few development methods depending on what the project is, these methods are available for companies to use to increase their productivity. The development methods I will be examining in this essay are Quality Function Deployment (QFD) and Requirements Analysis.
Quality Function Deployment is a method used in production which is aimed at meeting the needs of the customer whilst maintaining quality throughout the production phase.Requirements Analysis is a method which is used in software development to understand what the customer’s needs and expectations are from a proposed computer system.
Requirements analysis, also called requirements engineering, is the process of determining user expectations for a new or modified product. These features, called requirements, must be quantifiable, relevant and detailed. Requirements analysis is an important aspect of project management. After user requirements are captured in the form of interviews, research, questionnaire and surveys, the requirements are analysed, modelled and are documented usually by a Requirements Analyst before the stage of designing the proposed computer system begins.
(Source; System requirements analysis By Jeffrey O. Grady)
The process of Requirements Analysis is important to a software project because if there is not enough attention given to this process, the system may not deliver on what it was expected to do. It would also be a waste of money and resources to spend money on a system that does not meet the requirements of an organisation. The initial steps of the Requirements Analysis are to define a high level view of how the proposed system meets the business functionality requirements. The stake holders of the system are taken into account at this stage to assess how they will be affected by it. Use Cases, Class Diagrams, Data Flow Diagrams, Prototypes are a few of tools used to illustrate and better analyse user requirements;
Once the user requirements are analysed and well understood, they are documented to help design the system. It is important that the user requirements and the scope of the system are communicated properly to a team is technical and also to the end user. Problems can be identified and are easier to fix at this early stage which also reduces costs later if there were problems identified at a later stage.
Quality Function Deployment (QFD)
Quality Function Deployment (QFD) is a structured approach to defining customer needs or requirements and translating them into specific plans to produce products to meet those needs. The “voice of the customer” is the term to describe these stated and unstated customer needs or requirements. The voice of the customer is captured in a variety of ways: direct discussion or interviews, surveys, focus groups, customer specifications, observation, warranty data, field reports, etc. This understanding of the customer needs is then summarized in a product planning matrix or “house of quality”. These matrices are used to translate higher level “what’s” or needs into lower level “how’s” – product requirements or technical characteristics to satisfy these needs.
(Source; Quality Function Deployment: How to Make QFD Work for You by Louis Cohen)
House of Quality
The House of Quality is the most popular form of QFD and is used by a multidisciplinary team to interpret the customer requirements into a product that matches stated requirements at the same time as bearing in mind the engineering objectives and competition in the market for a similar product.
The House of Quality consists of six major components
Customer Requirements is well organised lists of requirement information gathered from customer or the end user this statement is also known as “Voice of Customer” (V.O.C). The company develops a focal point on what the customer wants rather than what they want to develop.
Technical Requirements is an organised set of relevant and measurable design characteristics of the product that is being developed to respond to customer requirements. Characteristics would be presented in an order.
Interrelationship Matrix the interrelationship matrix is used to calculate the relationship between the customer requirements and the engineering characteristics of the product. The correlation is measure by either symbols or numbers that show not only the relationship but also how strong the correlation is.
Planning Matrix the planning matrix allows a development team to compare their product against a competitor’s product and see how well it does. They will also develop a technical evaluation of prior generation products and competitive products. This evaluation will be based on the defined product requirements or technical characteristics. They will then indicate aspects where the company can make improvements to the product.
Technical Correlation (Roof) this is used to identify where technical requirements support or impede each other in product design.
Technical Priorities, benchmarks and targets this is used to record the priorities of the technical requirement and measure technical performance against a competitor’s product. A set of targets to be met by the new design are defined here. Develop preliminary target values for product requirements or technical characteristics.
QFD and Requirements Analysis compatibilities
I can find comparable procedures in both QFD and Requirements Analysis which could be used to produce similar projects. In both QFD and Requirements Analysis, user requirements are very vital, QFD and Requirements Analysis also use similar techniques to accumulate information from the customer or end-users so they can find out what the requirements are. In QFD, user requirements are is the most important element of the “House of Quality” tool. In Requirements Analysis a similar method is used to distinguish what the users requirements are, in Requirements Analysis data will be collected through methods such as interviews, questionnaires and research after this data has been collected it is then used to create what the user requirements are during the analysis stages. The requirements of the user/customer is important in both methods and are identified from early stages and checked up on to ensure they are met.
Similarities and differences between QFD and Requirements Analysis
QFD and Requirements Analysis are a structure of quality assurance techniques that are created to assist a company to achieve the requirements of their intentional users/customers. QFD and Requirements Analysis both focus on breaking down what user requirements are and all the way through each process checks are carried out to guarantee that the requirements are met. Requirements analysis requires a team effort that demands a mixture of software, hardware and human factors engineering expertise in addition to skills in dealing with people. QFD’s focal point is on product development whereas Requirements Analysis’s focal point is the Life Cycle Development which more commonly used in software development.
In QFD the product is to be compared to its market rivals whereas Requirements Analysis is just determined on meeting the expectations of proposed system. For example, QFD uses the customer requirements and technical requirements to illustrate the relationships and the “the basement” to record what targets that need to be achieved. It is the same with Requirements Analysis that after the requirements are gathered, they are modelled in different diagrams to understand what needs to achieved and then they are translated into system that meets the required functionalities by a technical team.
QFD uses the “House of Quality” model to exemplify data and ideas collected from the users/customer Requirements Analysis uses models such as Use Cases to do the same thing. Both methods, first stage is to search for the understanding of what the customer requirements are first instead of designing the product/service first.
In my opinion both Quality Function Deployment and Requirements Analysis are good methods used in project management. Despite the fact that they’re used in different company environments, both Quality Function Deployment and Requirements Analysis have similar characteristic that are used frequently in both methods, some similar characteristics they both have even sometimes perform the same functions such as establishing what the use requirements are. Both methods ensure that the final product / service meet the requirements of its intended user / customer. They are both designed to reduce labour hours to construct a product/service, costs and to guarantee a good quality outcome product to the user requirements specified .
Dr. A.J. Lowe et al., Quality Function Deployment. Pp.1-7
Simon Bennet et al. (March 2010), Requirements Analysis. Object-Orientated Systems Analysus and Design (4th Edition). Pp 180 -184.