In my experience, there is never ONE inventor. It's usually several people thinking along the same line. Sometimes publishing or talking about it to enough other people and it takes hold.
Then someone is daring enough to make a prototype and demonstrate "proof of concept". Basically, someone demonstrate that it can work.
After that, others fiddle with it until it works well enough to be a real application.
Final phase: if you are brave enough to invest a lot of energy and money to make it commercial you go for it.
Bringing something to the market is a definite team effort with a lot of contributors left behind and a few to make money out of it.
ecig is no exception.