Updated: Sep 13
Why do you need a Practical Problem Solving method?
Practical Problem Solving models are often shared online BUT the pitfalls are rarely well explained. In this blog we’ll be drawing on our own painful experience gained over 25 years, working across the world with hundreds of companies to illuminate those pitfalls. Here are the top 10 pitfalls as a list, scroll down for tips on how to avoid each.
The Practical Problem Solving (PPS) model we learned and successfully applied from working with Toyota group, has 7 steps. We’ll show you each of those steps and the most common pitfall at each step.
We’ll even “open the kimono” and tell you about our personal biggest practical problem solving failure - more of that later. At the end we’ll share 3 secrets to help you to turbo charge your Practical Problem Solving
The initial question, as ever, has to be “Why do we need a method for Problem Solving?”
There are three main reasons
We’re generally okay at containment when a problem happens, at mopping up
2) Short-term countermeasure
We're not bad at coming up with a short-term countermeasure (solution) but
3) Recurrence Prevention
Most manufacturers aren't particularly strong on recurrence prevention - they don't get to the root cause
A common problem is people jumping to conclusions based on previous experiences, leading to the wrong conclusions because something is different to last time.
A Practical Problem Solving method
So, here's the Practical Problem Solving method, showing the 7 steps.
You can see that it's a funnel shape reflecting the fact that we're going from a large area, vaguely grasped and explained, down to a really focused problem that we've solved.
The 7 steps to our Practical Problem Solving method
The seven steps are:
1) “Grasp the current condition”
Understand what's going on and find your tight focus point
2) “Locate process causing the problem”
That's the process where it's caused not where it's found in in your physical process
Using two tools often here, and for the next couple of steps - 5 why and fishbone
4) “Identify the probable causes”
Where we narrow down from our fishbone into what we think are the most likely causes – one, two or three of them and have a look at each in depth
5) “Identify the root cause”
What we as a team believe, through go-look-see observation and experimentation, is the root cause
Try solutions, one at a time
Using our PDCA cycle to make sure that we've got rid of the problem
Note the two things on the right of the funnel to look at. Firstly, it’s very important to protect the customer early and stop bad material or other problems flowing out to them. Secondly, you’ll see halfway down, after you've done a bit of investigation that you're ready to set a target: A “What?” by “How much?” by “When?”
A Problem Solving example: Fizzy drink canning factory
At Sempai we use a fizzy drink canning factory example as a Problem Solving example, along with our training materials, to help our clients start-to-finish through this process on their own shopfloor. Get in touch if you’d like us to help you this way. I’ll reference the fizzy drink can below.
10 Pitfalls in the 7 step Practical Problem Solving method
Let’s go back to the funnel model to look at the Problem Solving pitfalls
Step 1) - “Grasp the current condition” - Pitfall
The key pitfall here is NOT having a tight focus, having too broad a problem to try to solve. This is where our fizzy drink cans come in. On the picture below, having done some Data Analysis and using 80/20 thinking, if we just go after ‘dents’ our focus is too broad as there are actually 3 types of dents - 30 of one type, 8 of a second and 4 of a third. We’d pick the defect with 30 instances as it’s the highest (occasionally there are defects that have a lower frequency but cost more per defect).
Problem Solving is hard enough to do without trying to mix up and unpick a heap of variables affecting 3 different problems. If you try and do them all at once, you won't manage it. Picking 1 of the 3 to solve is good “Problem Framing”.
Step 2) - “Locate process causing the problem” - Pitfall
Critically, here you're not looking for the process where you FOUND the problem. It's where you identify that it's being CREATED. There's a very big difference between treating a symptom and a cause. Be careful that you’re not looking in the wrong spot.
Step 3) - “Investigate” - Pitfalls
This is often the area of biggest weakness, apart from Problem Framing in Step 1 above. When it comes to problem solving there are two major tools - Fishbone (aka Ishikawa diagram) and the 5 Whys. There are others, these are just the most common and useful.
The Fishbone and 5 Whys can be used together or they can be used independently. You don't always have to use both, but I'll come back to that later.
The first pitfall, in the Investigate step, is to brainstorm alone if you use a fishbone. Doing this, you only get one narrow set of ideas and experience. Involving other functions, like Maintenance for breakdowns, or Quality engineers for defects brings in other experts. Never, ever, forget to include the most important expert of all – your Operator. They know the process better than anyone as they live with it for 40 hours a week.
The second pitfall on this step is to remember is that you need a tight scope, a very tight problem well described. Not “dents” but a type of “dent” on a certain flavour of fizzy drink (if it’s made down a different line to the others!)
Step 4) - “Identify the probable causes” - Pitfalls
If you’ve used a Fishbone, you’ll then have maybe 20-40 post-it notes with possible causes on. You now go back over all of your post-it notes to identify the most probable causes. Don't get hung up trying to work out, scientifically, which are the right ones to pursue. Just agree as a team and pick the top two or three you believe. Then pursue them one at a time.
Also, don't try to critique AS YOU brainstorm as switching from one side of your brain (creative) to the other (analytical) gets the worst of both worlds. It’s mentally jarring and ideas won’t flow. Finish the brainstorm first, then critique the ideas respectfully.
Step 5) - “Identify the root cause” - Pitfall
Here you take your “probable causes” one a time and pursue the 5 whys – checking at each why stage whether what you’re suggesting is true. The pitfall here is simply staying in a training room or being rooted to the spot in the factory where you’re doing the Problem Solving. You can’t do either Step 4 or 5 in a training room or without looking at the process close up. Go-look-see and confirm on the shop floor.
Step 6) - “Countermeasure” - Pitfall
It’s really important to countermeasure (put a fix in place) for one thing at a time, otherwise you don't know which change got you the result - it's just a mix of variables. Don’t spend money too early, try solutions with old or scrapped materials, capital is scarce, thinking is free.
Step 7) - “Confirm” - Pitfall
Confirm is where we use our Plan Do Check Act (PDCA) cycle to see if our countermeasure has worked. To know if it has, you need something to compare against. So, at Plan stage, quantify the result you expect. For example, say after Step 4 “Investigate” that you have enough information to set a target. If you set that target at “20% reduction in dents in orange cans vertically across the bottom rim” and you only achieve 5% after countermeasure, you know that you’ve missed something.
Knowing when your Practical Problem Solving has worked!
There are two ways to check whether your countermeasures work:
You can recreate the problem at will
If you can turn it on and off you’ve sorted it
When you do your daily or weekly Data Analysis, this specific problem doesn't occur again or is greatly reduced.
3 secrets to turbocharge your practical problem solving
We promised earlier to tell you about our biggest ever failure. That was 20 years ago when being trained by a Japanese sensei. We locked a team, for two days, in a room with a vaguely defined problem and created the world's biggest fishbone.
A fishbone that we guessed and speculated about and didn't go to the shop floor enough, to grasp and confirm. That combination of a bad focus and too many guesses meant it was a waste of time.
As promised, here’s a bonus of 3 secrets to turbocharge your practical problem solving:
Secret 1: Speed
If you can get to a problem fast it's like a fresh crime scene for a detective. It's warm, there's a body, there's a smoking gun and blood on the floor. It's easy to crack. If you get there late it's like a cold case
Secret 2: You don't always need a Fishbone
Some people love a fishbone but, to a man with a hammer, everything looks like a nail. We only use it in certain circumstances; like if we can't recreate a defect or it looks as though there are multiple variables involved, or if there's a benefit to getting a team around it.
Secret 3: Avoid problems altogether!
This is the closest we’ll get to a silver bullet. Train your people to be able to spot abnormality early, get your shop floor organised through your 5s and standardised work, so that you can react when things start to go wrong, rather than when there's a problem.
Number 3) is so powerful we've built a module dedicated to avoiding problems in SempaiGuide, our digital lean toolkit for manufacturers. Check out the demo here.
That’s the major pitfalls covered. One last piece of advice is to follow the steps, use data and verify on the gemba at every stage. Otherwise, you’re just guessing. To accompany this article, we’ve created this video on our YouTube channel