I regularly get challenged about how much is too much or people say ” the effort required is beyond the potential benefit”. Or something to that effect. In principle there is no limit to how deep we should dive, how detailed we should be in our analysis & improvement efforts. In reality, there are always limits.
How far should you go? To what level of detail? Should I determine standard work to the hour, the 1/2 hour, 1/4 of an hour, minutes, seconds, milliseconds? Should I analyse every single defect to determine the specific root cause of each one? Even if I have 1000’s? Of course the answer is that “it depends”!
You have to start somewhere, those proponents of Six Sigma will say you want to have no more than 3.4 defects per million opportunities. But if you’re currently sitting at 3.5 Sigma, or 97.7% yield then you are still getting 22,750 defects per million opportunities. If you make 10,000 units a day, you should expect c. 230 defects per day. Is it realistic to analyse each one in detail? Possibly, but it is very likely that task is too much to ask your people to do, at this stage!
You start with where you are, look at making the next level of improvement, follow the PDCA cycle & move to the next level. Step by step, improvement by improvement you will get deeper & more detailed analysis until you are at that Nth degree that you fear will be too costly at the outset.
So the question about how far to go, when looking at how deep or detailed to analyse problems or establish standards all depends on where you are when you start. Of course you also need to consider the appetite for change, the time you have available and many other factors. As you begin to improve the appetite for change will normally increase, your available time should also increase which means your improvement will accelerate over time. Starting out is scary, people find all sorts of excuses to do nothing, quite often they are logical on the face of it. But a bit of pragmatism, coupled with some willingness to experiment goes a long way.
They say a journey of a thousand miles begins with a single step. How big that step is will depend on you. As Deming said “It is not necessary to change, survival is not mandatory”. One or the other will happen, resistance is futile.