Certain schools of thoughts have suggested the House of Quality (HoQ) has had its days. I think this is a mistaken view, however! Here are some reasons why:
An analogy to real house interior design is that empty space is equally important to filled space. The empty and low scoring space in a HoQ creates an essential floor/baseline perspective, without which the development team would be unable to gauge relativity and priorities for the higher importance areas. For example, if we, say, identified the 3 ‘most important’ customer requirements and just looked at them in isolation, then there would be no way of appreciating their true importance in relation to everything now invisible else that might (or might not) exist around them.
Even though customers rate something as being merely average important to them, the organisational context might benefit from evaluating the technical aspects that are in relation to this average customer requirement. For example, the customer requirement could impact on the organisation’s corporate image relating to environmental sustainability (what context) or the technical development could have opportunity for a commercial cost reduction (how context). Focussing the development planning solely on the top most important customer requirements, in such two example cases, would ignore an opportunity to improve the organisation’s commercial sustainability – without which it would be unable to serve any customers at all.
The empty space identifies where customers and stakeholders would not want us to focus, which in fact helps to prevent wasted efforts. The HoQ assures objectivity and cohesion, within a mixed design team of free-spirited minds. The empty and low scoring spaces help rooting out any individualistic subjective opinions within a team – i.e. it prevents someone from placing unfounded importance in them.
Many successful QFD practitioners never or rarely use the HoQ, but they would all have learned their principle skill through experiences with the HoQ deployment charts.
If you do not use the HoQ, then at least think as the HoQ.
The HoQ depicts the works that should occur in the sound mental process. Once all team members on a project are sufficiently learned in applying the mental process, then the documented HoQ is not essential. Using the documented HoQ, though, still helps assuring cohesion within the mixed project team. It can also help preserve knowledge, for the design handover to a different mix of people in the future design review. Think of the HoQ as optional, but be advised not to ignore its opportunity – unless you have something equally good or better to substitute it with.
You can download QFD and HoQ resources here.