There is a big difference between understanding the root cause of a problem and justifying it. And there's a big danger going down the justification route. And if we made a mistake and we want to make a different decision next time, it's much much harder to change the decision once we have deeply justified it was the right decision in the first place. Many of you have heard of the Toyota example. He's walking, executives walking along a production line, there's oil on the floor, why is there all on the floor because it's leaking out of the pipe, why is it leaking out of the pipe because the pipe is on too much pressure. So yes doing the five why's to find out why is important. You need to find the root cause and to fix the root cause but really work very very hard to stay away from justification. Find the root cause of the problem. We're trying to save money on filters, we got cheaper filters but the quality is not as consistent so sometimes we get over pressure, which puts oil onto the floor through the pipes. Okay, we buy better quality filters – yeah, but I'm trying to save money... Just don't go into that. Find out what the root cause of the problem is, try to do that quickly. Do not spend too much time there because if you spend too much time there you'll get into justification. You get into justification people become defensive. Once people become defensive it's really hard to make this step forward and you're the agilists. Step away, help people step away from their egos. Help them step away from the defense. Help them to step towards growth.