Tuesday, 28 April 2009

An Observation on the challenge of being a tester

Last night, Monday night, was shopping night, so I met my girlfriend in Tesco’s after work and we set about our weekly shop. I noticed recently that Tesco’s have altered the setup of their tills slightly and they’ve changed the arrangement so that customers are now able to scan their clubcards without the cashier having to do it and the card payment device was also moved toward the end of the till, in the area where you place your shopping in to bags – whether this is to make the whole process quicker, or just remove tasks from the cashier I’m not sure.

Anyway, as we went through the tills and completed bagging up our goods I took my Tesco clubcard from my wallet and went to scan it through the clubcard-scanner, which is situated at adult waist height, pointing slightly downward. “You can’t use that”, declared the cashier, “We’re not using them anymore.” “You’ve only just had them installed haven’t you?”, said I. “Yeah, but they realised that the laser beams which scan the barcode can damage children’s eyes so we can’t use them”, “you’d have thought they’d have tested that”, she then added. I wasn’t sure how to reply to that, as a hundred reasons why it might not have been tested flew through my head and I almost told her I was a tester, but then I’d imagine that information would have fallen on deaf ears – what did she care what I did for a living? Instead, I just laughed, thanked her, and wandered off thinking that this was a good topic for a blog post.

So what makes it a good topic for a blog post? Well, for me it highlights the difficulties that we have as testers. On the one hand, it sounds like whoever manufactured and tested this product didn’t consider the types of users that would be using or impacted by this device and for that there is no excuse. But there’s also the consideration that the barcode reader may have been through tens of test cycles, with masses of defects found & fixed, or maybe the test team only had a week to test the damn thing before someone told them it had to be released and so they spent the whole week ensuring it could actually read barcodes and transmit that data to the client, rather than test or understand how dangerous the rays were from the device.

As testers we have an almost impossible job because there will always be untested situations, scenarios or environments at the point of release and we never truly know if those untested areas will be the very areas which throw up a customer critical defect upon release. With risk assessments, and good judgement, we can have a very good go and ensuring we’ve removed most of the risk ahead of release, but there will always be that percentage of risk we release with, and that’s what we’ll always worry about.


Rob Lambert said...


Great blog posting.

I couldn't agree more with your thinking here. There are always going to be bugs in the system. I had it the other day where eyebrowse were raised when new bugs were found by a dev on the test stack! There will always be bugs and they will be found by all types of people.

I guess one thing that might have been missed during the testing of the scanner is the 'in situ' testing. This often throws up defects like in your example.

It's often very difficult to test, might not even fall to the test team to test it, might not even be considered.

Cool post. I always find it interesting and amazing as to where the inspiration for blog postings often comes from.


Philk said...

Supermarkets are great places for trying out your testing and observation skills - IF you have an understanding wife

When I blogged about a recent trip to an eye clinic and the problems they were having with their computers Michael Bolton did remind me that you dont know the full story - it could have been tested and found but was still decided to ship it

maybe you can take comfort from finding all these problems out there in the wild - always be jobs for good testers...

anne-marie said...

A very enjoyable and entertaining post! I hate a lot of the technology they use in supermarkets. Don't get me started on self serve checkouts...

I was thinking, that as a tester this would be so easy to miss. Even if you had taken into account all the users such as older people,teenagers, men and women, technically children are not customers, just innocent bystanders. Hopefully, the supermarket where you shop was being used as a 'beta' test and they hadn't rolled out the technology to all Tesco's.