You can understand why if you think about how division and multiplication are related. 12 divided by 6 is 2 because 6 times 2 is 12 12 divided by 0 is x would mean that 0 times x = 12 But no value would work for x because 0 times any number is 0. So division by zero doesn't work.
At the time of his death, Keith was suffering from emphysema and terminal lung cancer, as well as mourning the recent gunshot suicide of his 27-year-old daughter, Daisy Keith, ten weeks earlier. He committed suicide after he returned from a stay at a hospital.
Brian Wilson eventually had a nervous breakdown and left the group. Dennis Wilson died 1983 in a diving accident. In 1981, Carl Wilson, saying he had grown tired of the group's focus on nostalgia and lack of musical growth, left to pursue a solo career. But he later changed his mind and rejoined the Beach Boys, performing with them until his death.