James Dyson had never been satisfied with the performance of his vacuum cleaner. He noticed that it lost half its suction as soon as a bag was inserted. However, it wasn't until 1978, when he had to build a cyclone filter in a factory, that he had an idea for an alternative. Cyclone filter use centrifugal force and lose none of their suction. Why not, he thought apply the same principle to a domestic cleaner? His first prototype was made from an old vacuum cleaner without its bag. He developed his product and protected his ideas with patents. When he approached manufacturers to see if they would produce it under licence, they simply wanted to cheat him. He was so disappointed with the cut-throat business world that he decided to produce it to his own. In the meantime, he had to renew his patents regularly and almost went bankrupt in the process.