Their lives are more violent. When each particular fuel is exhausted, there is an abrupt drop in radiation pressure, which allows the star to gravitationally collapse enough to initiate the next stage of fusion. (There are also burning 'shells' of leftover fuel, but I'm going to ignore them.) Giant stars have a lot more gravity, and their fuel is exhausted much faster. The serious nastiness happens when you have enough gravity to initiate the fusing of carbon, etc. into iron. Iron quenches fusion reactions, so then you have a complete shutdown of the core. Everything left around it smashes into it and ignites in a massive detonation (nova or supernova). Our sun won't reach that stage because it won't be able to initiate higher level fusion.vincentm said:But why is it that more massive stars face a different fate than stars like that of our sun?
Feel free to put that into proper terms for me, Tiger.