Inner Ring has an excellent explanation with graphics of how the anti-doping process works.
http://inrng.com/2013/10/uci-bio-passport-tiernan-locke/
What's not explicit is the sports federation is the one ordering WADA to do stuff. If the sports federation doesn't make the requests (and pay for it) it doesn't get done.
Positive results can go unprocessed in the APMU as they did with Armstrong's 2009 red-hot samples with no consequences to anyone. WADA frequently discusses the problem of sports federations hiding positives. Not processing positive results in the APMU is just one way to hide positives.
http://inrng.com/2013/10/uci-bio-passport-tiernan-locke/
What's not explicit is the sports federation is the one ordering WADA to do stuff. If the sports federation doesn't make the requests (and pay for it) it doesn't get done.
Positive results can go unprocessed in the APMU as they did with Armstrong's 2009 red-hot samples with no consequences to anyone. WADA frequently discusses the problem of sports federations hiding positives. Not processing positive results in the APMU is just one way to hide positives.