if you have 1 inspector to review your products quality, he/she may review thoroughly. But there’s chance bad product will escape his/her inspection
if you have 2 inspectors, there are 2 possibilities:
A. The second inspector will review again the first inspector’s inspection quality, which means better inspection quality
B. The second inspector will think the first inspector has already reviewed it thoroughly, and only do some light inspection.
In many cases, B is more likely.
This is especially true if you add more inspectors. The more inspectors the more probability the next inspector will assume the previous one has reviewed it better.
This also the case for approval of proposal and reports.
I have seen many proposals who need at least eight (!) approvers. My estimation is only half of them actually read and review it. The other half will assume it has reviewed before and only scan for some key information, or others just simply sign it.
So, here are 2 rules:
1. More inspectors and approvers don’t help your business nor customers, always review it based on the value given by having them
2.Inspect the PROCESS, not the PRODUCTS. Inspecting products quality is too late and expensive.