What are Common Errors while Performing Root Cause Analysis (RCA)?

Common Errors in Root Cause Analysis
Samir Desai, Manager, India
4 common errors in Root Cause Analysis (RCA):
1) Scope: the scope of exercise is either too wide or too vague, for example delay in fabrication is chosen as the problem subjected to RCA rather than availability of manpower/material/design etc. This results in too many paths to follow.
2) Formation of Team: often the people directly involved in the area of RCA are the only ones participating in the RCA. This leads to the tendency of you scratch my back, I'll scratch yours. It also results in barriers to bring in any fresh / innovative approach to problem solving.
3) Data: RCA may be based on invalid data. The data provided to the team is accepted without much fuss, because to get valid data may end up in a supposed 'mission impossible'.
4) Conviction: sometimes members are disheartened and dejected from the very first move, because they believe that no matter what the out come is going to be, there will be hardly any implementation efforts towards the corrective actions that will be suggested.

Errors Before Root Cause Analysis
Bill Wilson, Analyst, Canada
Samir's answers are good, high-level examples of what can happen DURING an investigation (sounds like he and I could have been on the same investigation teams). I'd like to address a few errors that occur BEFORE the RCA effort even starts.
1. Evidence is disturbed, cleaned up, or discarded: to the extent possible, evidence should be quarantined and left as-is until the RCA team has had a chance to go over it thoroughly.
2. The RCA effort is started late: sometimes, it isn't obvious that a RCA is required. Other times, it is blindingly obvious that RCA is required but nobody wants to admit it. Either way, the longer you wait, the more difficult evidence-gathering and investigation will be.
3. The RCA effort is not granted priority from the beginning: if the RCA team is constantly having to fight for office space, supplies, time away from regular duties, witness time for interviews, specialized forensic/failure data, etc... Well, they're going to have trouble doing a good job.
Later!