If Anything, Please, Be Aware of your Granny Knots!

I assume you are a professional software tester. If that is true, then it means you are good at at least two things. You ask good questions and you are an excellent observer. So, here is a small puzzle. You’re ready? Ok, you’ve got 5 seconds time to come up with the answer. Below are two images of knots.

What - in your opinion - is the single most dramatic difference between the two?


Here’s one
500px-Granny_knot.svg copy
and here’s another one
Time is up! Did you notice the difference?

No, the most significant difference is not that the first image has rougher string edges, that is just because I am not such a good photoshopper and because I was a bit sloppy with the magic wand when I synchronized the color hues of the two knots. I decided to leave this small flaw in the image to mislead some of you.

The proficient observers among you have of course immediately noticed the different path the string takes:
1. Over-under-over-under-over-under
2. Over-under-over-over-under-over

The first knot is a so called granny knot and the second one is one that is called a reef knot.

And now comes the important part: Although both knots look almost the same, the first one (granny knot) is much inferior to the second one (reef knot) when it comes to the strength of the knot. The granny knot easily becomes undone if you pull on the strings. Or, in other words, if you challenge the knot, it falls apart.

Hah! And now it is easy to make the connection to software testing. There is a lot of testing that looks like testing but isn’t. It is just playing testing and not the real thing. These are the granny knots of software testing.

Some examples:
  • Calling something exploratory testing that is actually only mindless clicking about
  • Rigorously following the steps in test cases without switching on the brain
  • Any record and playback test automation
  • Reporting tons of metrics that fail to answer any meaningful questions
  • Talking about 100% coverage without answering: “Referring to what?”
  • [your own example here]

If anything, please, be aware of your testing granny knots. Examine your testing practices thoroughly in order to identify areas where you only superficially test or where your practice is simply wrong. Stop doing them or, if possible, correct them.

BTW: Are you somebody who is constantly re-tying your shoe laces because they undo themselves? The reason for that could be that you use a granny knot instead of a reef knot. Have a look at this instructional video to find out.