I Let AI Do My 5-Why Analysis — Here's What Happened

> TL;DR: Root cause analysis is the hardest part of quality engineering — not because the tools are hard but because bias is invisible. I tested an AI root cause tool on three real cases. Two of the three it found causes I would've missed. Why Root Cause Analysis Is So Hard 5-Why, fishbone, fault tree — the tools are easy. The hard part is not jumping to conclusions. Your brain want to find the simplest explanation and call it done. That's why operator error show up in so many D4 sections. The Experiment I took three old 8Ds where I knew the real root cause. Pasted just the problem description into the AI tool. Case 1: Solder joint cracking — The AI suggested thermal cycling, which was correct. But it also suggested moisture sensitivity of the PCB material which I had NOT considered. Case 2: Motor bearing noise — The AI spotted that the grease spec had changed recently — supplier switched to cheaper grease. I missed that. Case 3: Torque variation — AI got this one mostly wrong. Not terrible, but not right. The Bottom Line AI root cause analysis is not a replacement for thinking. But it...