Armstrong would get IV's of low doses of PEDs right after doing his piss tests, and claimed they were part of his cancer treatment. That is kinds like how they do shit in Horse Racing. The horse gets a shot of X amount, Y days before the race, so the after race test doesn't show a high enough level of Steroids or pain killers to turn up hot.

The top guys are all paid well, for them it is more for ego than greed.