Just the other day, I tweeted that a good problem solving strategy is to compare the best and worst and look for differences: different machines, different people, different suppliers, different customers…etc. A follower tweeted back, “Why the best and Worst? I replied that you want to look for obvious differences that could lead to the root cause of the problem. I have used this strategy many times with great success!
This morning I read an article about a maintenance group that began a project on failing pumps. In their efforts to determine reasons for pump failure, they noticed that pumps with few or infrequent problems were those that were never shut off. In fact, one pump that had never been shut off had never given trouble in seventeen years. This led them to see that by keeping pumps running they could add years to their longevity.
At a previous employer, we were having high scrap rates on a certain product. Just by comparing the best and worst, we were able to solve the problem in minutes. One operator was using an incorrect method that no one was able to detect until a best vs worst comparison was made.
So, whenever you can make this comparison, think about what is different about the worst that makes it different from the best.
Let me know if you have used this strategy and if it worked for you.