If you have an inspection area where you are inspecting for three defects, you would count this as three opportunities only if you check for all three defect types on each part. If you only count one defect, then scrap the part, you would consider this to be one opportunity.
Counting opportunities is a way to translate your defect rate from a per unit basis to a per process basis; translating DPU into DPMO and Sigma level. It is necessary if we want to compare goods and services that are not necessarily the same. For example, two customized printing processes could both have a dpu rate of 0.14. If process A has 4 opportunities per order, the dpo rate is 0.035. If process B has 8 opportunities per order, the dpo rate is 0.0175.
Complexity is a measure of how complicated a particular product or service is; a more complex process will have more opportunities. While it is difficult to truly represent complexity accurately, generally complexity can be reasonably estimated by a simple count. This count is referred to as an opportunity count.
For example, a circuit board with 25 parts and 48 solder points is a more complex board than one with just 12 parts and 22 solders and it will have more opportunities for defects. The opportunity count for the first example is 25 + 48 = 73 and for the second example is 12 + 22 = 34.