For felos...it is an over and over again thrill, ohhhhhhhhhh the ultimate GODLIKE power.
For MS, the exquisite pleasure in providing a torturous, fully under his control so called existence for terri and at the same time getting to render punishment of the cruelest sort upon her family has apparently been a great thrill in and of itself...now that the money is running low, a bit of the fun is gone, and now it is time to enact the final blow, death. Not to relieve terri, of course, because that would not be any fun for MS to contemplate and relish, to help her out, that is, but oh the exquisite joy in watching the schindlers lose their daughter forever....including cremation and a quick flight out of state to a burial. The final blow.
Imho, anyway.