What the diffrence between BC7_QUICK and BC7_USE_3SUBSETS compression flags in DirectXtex lib?

At nan opening I thought they were for illustration Fast and Fine compression of Photoshop's Intel texture tools, but I later recovered nan instrumentality uses a different compressor called Intel's ISPCTextureCompressor,

So I want to cognize does those flags impact nan image value successful immoderate way? Is location a use of utilizing them?