When you are not an athlete of international level, the only authority going to test you OOC (and not for many times in one year) is the National antidoping agency.
At the end of 2016, Sondre Moen had a PB of 2:12:54 in 2015, that gave him position 325 in the World. In a similar situation, WADA and IAAF are not interested to do blood tests, and this is what many posters don't understand when we speak about Kenyan athletes for 2:08 who are caught doped in competition : NEVER these athletes can be tested OOC in Kenya, because in the same position there are maybe more than 300 athletes, and there is not budget enough for testing (maybe with a minimum of 3-4 times) all these athletes. If you want to test OOC all the Kenyan athletes of international level (out of top 30 who are in the whereabouts system) for a significative number of times every year, you can have more than 1200 tests only for second level athletes, with a cost of about 800,000 USD (that of course nobody has).
So, for these athletes there is no way of any prevention, apart giving them a different education about ethic and physiological point of view, and, if somebody wants to dope, the only opportunity comes in the antidoping tests IN COMPETITION.
Why Sondre is tested more than Galen Rupp ? If you go to see in 2018 the list of all his tests, you can see how the testing authorities frequently are different : IAAF-AIU (we can read this as WADA), ADAK or National Agency.
Normally, IAAF-AIU doesn't go to test athletes in their Country : for that goal the authority is the National Antidoping Agency. But, when some athlete in the whereabouts system trains abroad, the IAAF-AIU can work on international level for testing athletes of every Country, training in different parts of the World.
IAAF-AIU can be considered as the Interpol Police : in one Country there is the local Police, but if an American gangster escapes in Germany or in any Country with the same agreement, he can be wanted by Interpol, and his crimes are evaluated under the law of his Country.
The main reason that pushed WADA to consider Kenya a Country not compliant was exactly this one : the Kenyan Government never gave any economical support for the domestic antidoping tests, and for the Kenyan in the whereabouts system (between 130 and 150 depending on the year, which is the HIGHEST number of athletes in the World for one single Country) ALL THE COST of the test was at charge of WADA, with a clear unfair situation compared with what happens in other Countries.
But to say there were no tests is something deeply wrong, because ALL THE TOP were tested OOC more than 4 times in one season, of course with too high cost for WADA. To declare Kenyan NOT COMPLIANT and risking the Olympic Ban was the only way to put Kenyan Government in a corner, finally obliging it to giver a right contribute for the tests in Kenya.
About the athletes, normally, when an athlete "explodes" with something nobody could previously foresee, all the antidoping agency put him under a special lens, increasing the number of tests in order to become more sure he is clean. If after 2-3 years all his tests are very comfortable, and there is no suspicion that he can use something illegal, step by step the number of tests becomes smaller, and 3-4 tests per year can be enough for controlling his behavior.