WADA can’t make competitions fair

Recently Alan Abramson wrote an article where he noted whether tests conducted by the World Anti-Doping Agency (WADA) were efficient.
The WADA conducts more and more tests for steroids and other performance-enhancing drugs every year. It seems that those that apply steroids and/or other related drugs are caught. One may believe that the world of sports and bodybuilding will be soon cleansed from intake of banned products. For example, a lot of tests for banned drugs have been conducted at the 2012 Summer Olympics.
But certain questions appear here. Are these tests sophisticated enough to catch any sportsperson who dopes? Are these tests effective?
Let examine results of certain tests. In 2010 the WADA published statistics according which 258,267 samples were analyzed by 35 WADA-accredited labs. Out of these samples 4,820 results were atypical findings. Circa 60 % of positives indicated about steroid use. Numerous positives were for cannibinoids. 10 % positives indicated about usage of marijuana. As you observe, just 60% out of those who administered forbidden medications applied steroids. Is it real? Don’t show the results of the tests that the WADA doesn’t do the job suitably?
Dick Pound, the former president of the WADA, believes that at least 10 % of athletes that competed at the 2012 London Olympics took steroids. He confirms that those steroid users that are not clever are caught by anti-doping agencies. He also confirms that a sportsperson that has been caught doping will fail an IQ test. He adds that only unwise sportspersons don’t avoid detection.
Thus, when you read that the WADA has conducted many tests to make sports clean, think whether these statements are true. Is able the WADA to make competitions fair? Why does the WADA publicize about number of tests?
It seems that the WADA just wants to convince people that the job is done properly. The WADA put efforts to secure future funds. This is the reality.