What were the drivers behind his innovation?
It has been said that many of his inventions were inspired from his time as a stuntmen - this line of work has made him friends that had suffered life changing injuries as a result of their work; and he wanted to change this and invent devices that would help people with disabilities in their everyday lives.
In terms of the clockwork radio specifically, he was driven by the lack of access to important health information to people African countries, which has lead to the spread of AIDS due to insufficient public awareness about the syndrome. His clockwork radio invention was in direct response to communicating this information to the people of Africa, where affordable energy is scarce or non-existent.
Why was his invention so useful/innovative?
His invention was useful and innovative as it helped many learn about overcoming the epidemic of AIDs in places where it lacked access to education. His invention was powered by muscle alone, and did not require any electricity or batteries to be powered, which made access to health education increasingly accessible to remote communities.
How did Trevor encapsulate the role of the lone inventor?

Was his product a commercial success?
The clockwork radio had a difficult startup because it was rejected by many companies for manufacture on the notions that it was 'not right' and 'unsuitable for development'. However, Trevor overcame this by staying committed to the innovation of the product and persisted, hoping that someone would take interest in his idea. In 1994, Christopher Staines offered a potential partnership that lead to full production and a factory in South Africa. Here, Christopher can be seen as one of the most important people in the commercialization process - and that is a product champion.
Africa has a population of some 600 million people and radio is recognised as one of the most popular and accessible ways of spreading information.

Baylis argued that the British legal system failed to protect inventors, leaving them open to exploitation not only from imitators, but venture capitalists, lawyers, and other in the commercial business world.