We are living instances in a simulated deterministic world.
The instance is disposed after it fails to maintain itself (our death).
Our body cells degenerate with time, that's why we get old, brain cells are the awareness engine. With time, parts of your body get older, our cells always in a split process "meiosis", and withing each split the new ones are older (it is a lossy process).
With time and time, our organs deteriorates.
Our body is chained ecosystem, the first organ that starts to fails affects the other, until brain cells are affected => once it fails we are technically died.
e.g. old lungs organ failure, oxygen miss, brain cells die...
e.g. nervous system parts fails, you may have memory loss...
With hope and advancement of science, if we succeed to regenerate and refactor our organ in a continous awared biological process, death will be only a matter of a bad incident or an accident.
RE: Today's dream: My dad was dead