Complex sentence: In most cases, serving on a board is not a career unto itself, but board members often receive remunerations amounting to hundreds of thousands of dollars per year since they often sit on the boards of several companies.
Split into simpler sentences: In most cases, serving on a board is not a career unto itself. Nevertheless, board members often receive remunerations amounting to hundreds of thousands of dollars per year since they often sit on the boards of several companies.