Wasn't part of the fuss not just about the plagiarism, but in an interview about half an hour or so before she gave the speech she was saying how she wrote her upcoming speech with a little help from a few people. So it's that she chose to plagiarise, or she's doing that other rather common thing of lying to the public.
Sure, it's all being rather blown up, but it's part and parcel of all the little things that show good foundations are not there to be built on.