Exploring Process Variability in Six Sigma

Variability is inevitable in every process, no matter how hard you might try to adjust your practices to avoid it. In some cases it’s even inherent to the design of the system and is just something you will need to account for in your planning; in other situations, it’s less predictable and something that will require a lot of careful attention to ensure that things will go smoothly. It’s important to know what your own situation is like, and which category you fall into, so that you can take adequate measures in dealing with variability in your own company’s processes.

There are various tools to track process variability and to ensure that it’s properly accounted for in your future operations, and you should explore this area with enough attention if you want to ensure that you always have a proper overview of the current status of your operations. Especially when it comes to an organization with heavy use of computers, you can hardly have an excuse for not having proper data collection and retention systems in place. Of course, being able to work with that data and process it in a meaningful way is just as important, but this usually goes hand in hand with collection systems.

Recording and Storing System States

A great way to ensure that you have a proper overview of the current process variability in your systems is to put appropriate systems in place to capture all relevant information and store it in an easily accessible way. The last bit is important it won’t do you any good to have the best data collection system in the world if you have no means of working with that data and finding interesting patterns in it. That’s where modern analytical systems come in play.

You can actually gain a lot from deploying something like that to your current operations if you’re still relying on manual analysis to get an overview of what’s going on. People are good at spotting patterns, that’s true but this only extends so far, and there comes a point where you will need automated systems to recognize the kinds of patterns that actually matter for your operations.

It’s also important to sanitize the data every now and then in order to ensure that the sets you’re working with are fresh and relevant to your current operations. A common problem that can be avoided in this way is a situation where you’re making incorrect market predictions just because you’re working with outdated information.

When is Variability Unavoidable?

There are situations where some variability will be practically built into the way the process works, as we said above. Learning to recognize and deal with those situations is just as important as avoiding variability in other areas. However, there is no strict system of rules that you can follow to get there, unfortunately. It mostly boils down to intuition and having enough experience in your specific industry to know when something is not right.

Once you do have that intuition though, things tend to work much more smoothly. Knowing that a process is supposed to deviate from the norm on a regular basis can allow you to focus your research efforts into another area of your operations, and you can even start to add the variability to future forecasts about the output of that process. That way, nobody will be taken by surprise when these things happen, and you’ll be able to proceed as usual without any interruptions to your workflow. And that, as you’ll quickly find out, can be an invaluable asset in your operations in the long run.