Inventions : A dime a dozen

Although someone comes up with a new idea that seems to be great, it is not valuable until that the innovation appears. In other words, invention can mean nothing without the idea itself. For example, the incandescent lightbulb was originally invented in 1802. However, it took more than 75 years that people can get real benefit from the lightbulb. Thanks to Thomas Edison with the considerable technical and commercial talents, the lightbulb can implement a practical application, which allows people to do activities like a daytime. Even then, the widespread diffusion of the lightbulb took additional decades-and has not yet occurred in many locations around the world. Accordingly, the inventions are "a dime a dozen" because the invention itself has difficulty to making an effect.