If I had to place a bet on why one might catch fire, it would probably be the combination of constant abuse demo models take, along with the presence of a defec

If I had to place a bet on why one might catch fire, it would probably be the combination of constant abuse demo models take, along with the presence of a defective battery, and finally a crapload of free apps piling on background processes that keep the CPU and chasis at an elevated temperature, stressing the problematic battery. All this combined with the final, fatal recharge cycle which added additional heat to the battery, and poof!