Appraisal or Prevention! What's better?

In-process inspection inside a company is typically a 'cost of appraisal' for the company. 

Is the same true for a supplier, for her 'visit to customer for in-process inspection while installing the supplies' at customer's end as a part of the supplier's process!?

It's True, the said installation being a part of the process of the supplier company. 

It's, however, a 'cost of external failure' for the supplier if installation is customer's responsibility and she finds a defect/error in supplies while doing so. Otherwise, it's the 'cost of prevention' for the customer. 

In either of the cases, be it appraisal or prevention, it is a COGQ (cost of good quality) anyway as a part of the COQ (cost of quality)!

One may have to strike a balance though, while deciding upon spending on the latter, meaning on the visit to customer as a part of the process itself, especially in case of high-impact high-value industrial products. 

In any case, the COGQ in general and the other 'costs of prevention' in-house, in particular, may prove to be most beneficial and highly profitable at that.

Why not try validating this statement by calculating the components of Cost of  Quality, for a failed item that reached your customers in past!

Calculating the Cost of Quality (both the COPQ & COGQ), classifying the corresponding components as Tangible (Visible) Costs & Hidden Costs, and comparing them might help.

Also read a few relevant blogposts hereunder:

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