Perfect room

I read a magazine few weeks ago. In the introduction there was a sentence: "If you light every inch of a perfect room, then you will find a dead fly in some corner and an hungry spider eating it."

I started thinking about this sentence and realized something. Though this sentence came from social magazine, I realized that it can be implemented very well into Software testing. No matter how much effort you put into testing your software, there are still bugs in it. Sadly however I've heard quite too often phrases like "Why didn't you find them at time?", "Why didn't you do enough testing to find these bugs?" etc.

Project Managers, Analysts and Customers who don't understand the conception that software isn't just mathematical formula with small amount of limited results. They tend sometimes to blame Testers for being responsible for not finding all bugs in software. But we didn't put them in there! It is like throughing handful of needles into haystack, not saying how many you throw in and expecting someone with limited time to find them all.

Yes, during any given time we can tell with certain amount of confidence that it works with specific scenarios under specific conditions. Yes, with more resources (both in time, tools and skill) we can go through more scenarios and understand more and more about the software. But never can we check every last possible combination and be 100% confident that it works. I listened to Michael Bolton and James Bach conversation about "What to do when first step in test case is "Reboot your test system"" (Listen it here) and there was something said that called for my attention: "You can never run the same test under exactly the same conditions more than once. If you think you can, you don't have enough fantasy to understand.".

Of course people are upset that there are bugs within the system. I recommend to read this Michael Bolton posting about how a beesting can be just annoying or either it can be lethal. But if you give us enough time to use our skills, we will try to make sure that there are no such bees in the software that could kill it. But with limited time we can only find limited amount of such bees.

Note: Found the link, I have to apologize since the posting was in Michael Bolton's Blog instead. I've been trying to catch up with things I've missed with a year and with 5-6 blogs it gets a little out of hand. Will try better next time. Promise :)