What is the White House's rationale for recent high-profile personnel changes at agencies like the FDA and Social Security Administration?

The Trump administration is seeking to fill administrative roles with individuals who clearly align with their agenda. White House officials repeatedly emphasize their goal to root out waste, fraud, and abuse in government agencies. In the case of the Social Security Administration, they've suggested they suspect tens of millions of individuals are inappropriately receiving funds despite being deceased, though no evidence has been presented for these claims. The White House has empowered Elon Musk and his team to identify inefficiencies within federal agencies. While previous administrations have claimed they would eliminate government waste, the current administration insists they will actually follow through and prove it, despite the lack of transparency and specific evidence provided so far.