The 8th house is the darkest house in astrology, representing death, the underground, and the cremation ground ("Shamshan"). Jupiter (Brihaspati) is the planet of supreme wisdom, expansion, and divine grace.
When the ultimate light of Jupiter enters the ultimate darkness of the 8th house, magic happens. Dr. Sharma explains that this person has the miraculous ability to find massive success in the worst possible circumstances.
Even if you throw them into a "cremation ground" (a dead business, a ruined project, or a hopeless situation), their Jupiter will beat its drum of victory ("danka baja dega") and they will build a "Golden Lanka" (an empire of wealth) right out of the ashes.