Setup and Hold time

CHIP : In chip design in between two flip flops we have some combonatorial logic. Output of first flip flop is combined with few other signals which are new to this stage and then become a new signal which goes to second flip flop. We need to make sure that this final signal should reach before clock edge of second flipflop (setup time) and should be stable after certain time of clock edge (hold time). We need this stable period because there is some logic inside flip flop which needs to give a definite answer at output : 1 or 0.
If Signal changes its value during this window then output of flipflop becomes undeterminent(metastable). And it may take more time to go to 0 or 1 eventually. Setup time is generally bigger than hold time in value.

LIFE: In our life also flip flops corresponds to starting of our different stages of our life. Like child age, Teen age, young , marriage, old age etc. When we enter into one stage (teen age flip flop) then before entering into young stage (flip flop) we are in teen age logic and apart from what we learnt in child age we get some other new factors involved like college,new friends, other priorities.. Before entering into new stage (young age) we need to make sure that we have stable state(setup time), i.e. we have finalized results of all other factors on us during teen age stage, so that during the stage transition we should know what is our stable state is and what should be our next state in next stage.
Also, one we have taken decision then we should keep our input of young age the same one(hold time) so that we should get some time to analyze that whatever decision we have taken is good. If we change our input of young age then it may make us in confusion state (metastable state).
Similar to chip design our setup time of transtion from one stage to other stage is also greater than hold time.

LEARNING :We should be stable during our major transition of phases/stages in life.