In Sonnet 3 death is viewed in a way that is very similar to how it is presented in Hamlet. In Act III scene 1, for example, Hamlet in his soliloquy describes death as:
The undiscovered country from whose bourn
No traveller returns...
What is key about this description is that Shakespeare uses a metaphor
to compare death to an "undiscovered country," which adds an element of adventure to our understanding of death, but ultimately, there is no return from this new land that is waiting to be discovered. Death is final.
In the same way, Sonnet 3 ends with a stark reminder of what death represents. As the speaker urges his beloved to procreate and have a child to act as if they do not their beauty will die with them, forgotten and not remembered:
But if thou live, remembered not to be,
Die single and thine image dies with thee.
Death again therefore is presented as an ultimate end, something to be feared, as it also represents the death of the beloved's "image" if they do not have any children to bear their resemblance. Death in both texts therefore is presented as a force that robs and takes life, and as a force that cannot be cheated or gainsaid. The emphasis in both of the quotations above is on the finality of death.