Every once in a while there comes a task of testing some small change or a simple feature. It is small enough to be tested in few hours, very easy to see if it misbehaves. Specifications are also up-to-date. So you plunge in, covering possible risks and – voila – done.
And then. Two weeks later. It comes out that, due to some design irregularity or technical issue with the 3rd party electronics, the small functionality was awfully tricky to implement and in all possibility has an effect on the core functionality of the product. And then you are in trouble.
You probably have to do a lot more testing. Assessing the situation, demanding code inspections (which don’t give more detailed info than ‘might have an impact here’), analyzing old threads, etc. And you do not find big problems. You seem to be in the clear. Phew.
But what happens next is that all your further efforts are more focused, you are in ‘alert’ mode as the uneasy feeling stays. And this makes your testing a lot better.
So, I have found that whenever I am feeling confident about the product – that we should have clear sailing from here on – I need to talk to developers.They always have something to tell me which might horribly mess it up. Things, that are not usually told to project managers or testers, as those are development problems they need to solve, and usually they do solve them. But knowing those issues helps to put me on the ‘edge’.
Talk to developers about their problems and triumphs, they like to share and you get headache 🙂