The fact is, while some parties are known, others aren't. When politicians are controlled by blackmail, you don't need to know the politician, you need to know whoever holds their blackmail. With multiple parties being simultaneously controlled by multiple entities with different motives, it's a difficult game. You also don't know which ones will follow orders from whom, if given conflicting orders by different handlers. You have to place each one in a situation where their true nature comes to the surface. That's what he was doing. Each pick not only needs to be analyzed for their integrity and ability to perform the job, but also analyzed as to whether they get approved by other politicians that are known enemies.

If he brought in total outsiders or trusted military, none of his picks would've ever gotten past Congress. Reagan had that problem big time, and was less effective because of it, saddled with entrenched bureaucracy who pretended to be on his side but secretly sandbagged his cleanup efforts. This plan knowingly took in a ton of bad actors to use them temporarily, sift them and replace them. Trump fired more advisors, executive staff and cabinet than any president I can remember. Genius of temporary appointments and last minute switcheroos.