Camera profiles and raw converters

We all know that Camera Raw uses a modified working color space with a gamma of 1 and the colors of Prophoto RGB. But when does the conversion from the camera profile to that color space happen? At the time of import? And why does Camera Raw use an intermediate color space? It will be converted to one of the four color spaces at the time of export? And what about other converters? Capture One uses a camera profile and you can export the file in that space. Does that mean that the editing is done in the camera color space? Stefan