It was Walter's family that drove him to get into the meth business. Before Walter was diagnosed he and his family were very close, which is why when he found out that he had a short time to live he had to act fast, think of any way to make money quickly, he was desperate. This desperation is seen when Mr. White tracks down his former student, Jesse, who he knew was into the drugs. even though everything Walter was about to do was against what kind of a person he was, he knew that he had to do it for his family.
The cooking became much more about the families future, it took over his life in a negative way. after he and Jesse had cooked for so long he not only met his desired amount of money but he made hundreds of thousands more, the product that they were producing was so pure that he was asked to continue to cook on with the best equipment avalable, provided by the head of Los Polos food chains.
Becasue his treatment had a positive effect on his cancer his life expectency was prolonged and the meth cooking then became much more frequent. once he and Jesse were hired by Polos everything changed, he was making more money than he could have possibly imagined from when he came up with the idea to cook. The power created from all