The execution of an idea is just as important as the idea itself. It has a huge affect on whether or not you can sell your idea to an audience.
Most of us, for example, have seen the special features on our favourite Bluray or DVD. You will very often hear the 3D and special effects people say something like, "we aimed to make sure no one noticed the effects". This approach enables the story to be absorbed by an audience because they are not distracted trying to work out what looks real and what looks fake. Good effects sell the story and are rarely noticed.
The correct execution of your an idea or message, whether it be on television, radio, web, or in a magazine will draw an audience in and help them focus on the message.
For example take a look at what goes into editing this television commercial to convey the sense of a premium product while endevouring to make any special effects or treatments look natural.
It is important to note that not every television ad or project needs this level of polish, but it is important to aim for the appropriate level to best sell your message.