More Definitions of Quality Rikard Edgren
I grew up in a small “town” in Värmland. Outside the village, most people live in isolated houses/farms on the countryside or in the woods.
If you’d ask one of these persons what quality is, they would answer:
dä ä väl att fôlk töcker att dä ä bra
(guess it’s that people like it)
This is actually quite a nice summary, well in line with Jerry Weinbergs “quality is value to some person”; but it doesn’t help us a lot as software testers (except clearly pointing at quality being something subjective.)
I read Marlena Compton’s blog post on quality and art (http://marlenacompton.com/?p=605) and realized that quality, like (good) art, isn’t so hard to distinguish when you see it, at least not if it’s quality for yourself. So here’s a try at a slightly more fruitful definition for testers:
quality is value to me, people I know, or people I don’t know
If I am a customer, or am using the software with a customer’s understanding and needs, it is not difficult to understand what is important and needs to be fixed.
If I know a lot about the customers and the area where the product is operating, it is also not so difficult to evaluate if the software is “good”.
If I don’t know the users, I can only take guesses at what quality could be for the product.
So as testers we should try to get more “Me” people, maybe by using the product internally (eat our own dog food, drink our own champagne/pommac), and we should try to move “Don’t Know” to “Know” by learning, using Personas, learning, visiting customers, learning etc.
But when reading TASSQ magazine from 2006 (http://www.tassq.org/quarterly/docs/TASSQuarterly0604B.pdf) there were some definitions that said that we don’t have to be so subjective in the quality definition, e.g. if it is possible to say that a car with certain attributes is of high quality, why can’t we do it for software.
This leads me to another try:
quality is more than the subjective sum of relevant quality attributes like
capability, trustworthiness, usability, security, performance, compatibility, entertaining…
You can use many, many different quality attributes, and the importance will differ for products and types of users, but by thinking about the right ones, you will get a hint on what would be better or worse quality.
One caution: quality is “more” than the sum of the attributes, there is something unknown and magical that some software has, and some don’t.
All in all; I don’t know what software quality is, but I know that it is very important and something we should continuously think about.
We won’t come up with something universally true, but it can be useful.