Just a few kilometres from where I live there is a great spot for walking – with or without a dog. It is quiet and traffic free, with spectacular view across the countryside. The grand perspective across surrounding countryside was likely more appreciated in earlier days; it is the site of a 2500 year old hill fort with the earthworks still very obvious and impressive despite being worn down by the centuries.
One of the things I love most about the site is how very little we really know for sure about it, the people who built it and how people actually lived there. There is a goodly amount that can be inferred from what is left, but when walking around it you do feel that we can only know a little, presume a bit more, guess a good chunk and – importantly – accept that there is much we do not know and will never know.
It seems to me that this acceptance of what we do not know, and more importantly what we cannot know, is a hard thing to do, and one we as a society are getting rapidly worse and worse at. Maybe we expect too much? Certainly if we were to take too seriously some of the criminal investigation TV programmes we see we would believe we can know everything – where a small nick in a 10 year old bone can lead to complete diagnosis, arrest and conviction in a single 45 minute episode.
Of course, real life is rarely like TV, but there does seem an increasing belief that we can know everything, which I doubt is justified by any kind of objective assessment of our own lives. It is almost as if we believe that we can find out anything we want – or that we can ask an expert who will simply tell us what we need to know. In fact there are – even now –many things we do not know, and will never know. That is true in most aspects of life – from what our children get up to through to configuration management – the trick perhaps is to accept that and make the best use of what we can know. That includes realising that what we do think we know may not be 100% accurate – but that is it still useful all the same.
Way back last century, I studied Physics at University. Well, I was supposed to be studying Physics, I certainly recall making TV programmes and being in the bar – somehow my memory can’t have stored all the time I spent studying.
But one thing I do recall was that in the lab work the answer ALWAYS had to be expressed in terms of the uncertainly – the temperature of the liquid under examination was not 23 degrees – it was something like 23 º ± 2º. Being realistic about your accuracy was seen as a critical aspect of any data.
And rightly so. It is of critical importance, because if we just think that everything we know is an absolute black and white fact – then we will make bad choices. Being aware of the accuracy does – or certainly should – affect our decisions. If you want a common example of where we get it wrong then think about some of the customer satisfaction surveys you may have seen in your time. Even a good customer survey will show only a good indication of opinion, attitude and desires. It will never be totally accurate but it can be useful – especially in terms of trending.
And availability is about averages, happenstance and luck – so a 99% availability does not necessarily mean 99% customer service delivery – because you don't know when that bad 1% will happen – and so don’t know what affect it might have. Is it going to be peak period or quiet time? But it can help us decide how to build and manage systems – and lead us into sensible risk/benefit decisions. In fact getting on and using the data you do have might be a good mantra? All too often we seem to seek data for its own sake rather than because we see a need for it.
Those people who built that hill fort 2500 years ago certainly knew a lot less facts and data than we do. But they knew what they needed to know to do a good job and made great use of what they did know. Hopefully we can use the knowledge and data that we have without being distracted by trying to get even more? And then maybe our constructions will also still look good in 2500 years.
Maybe you can spot some places where you are spending time, money and worry tying to get ever more precise data that you don’t really expect to use. Or more likely you can see where – or your management – take as absolute data that you know is actually just an estimate within a significant range of values?