Actually, 1000dppm (99.9% defective parts per million) is not acceptable except for hobbyists. Typical commercial manufacturing requires <100dpppm due to the number of components and cost of returns. This can be met quite reasonably with statistical sampling and process controls. Every single IC gets tested, it's just a question of how thoroughly and whether the control limits are set well. You need to do R&R studies, but the infrastructure/procedures are usually available to approach 6sigma (even if it's a bit hokey).

Where this is going a bit nuts is that that it's hard to make 100 gold contacts last for 1000 compression cycles at 1 dppm (better than 6 sigma!). That requires a lot of excess maintenance on the test infrastructure! That will be expensive... and your assembly connectors/SMT is likely orders of magnitude higher defect rate than 10dppb so it won't improve final assembly performance.

Also, I think you need another 9 on that 99.99999% to hit 10ppb and realistically 2, if you want to have an acceptable yield rate, and 3 on the test equipment since they are used 10k times every day.