Som people are picky in general, some have special needs, ideas or products they are very choosy about. You want to make an impression on them? well, maybe it is time to resort to a picky voice.
Who are picky people? It is essentially people that are carful, sometimes even too carful when they choose or accept things. It could be a very sensitive matter, but it could also be a very common daily thing in their lives like a soap they are going to use. Whether it is part of their nature, something they gained throu experience, or both, it doesn't matter. It will take some hard persuading to make them chose something or make up their mind. In those situations, people trying to help them out need to think like they do, but also speak aloud with what sounds like their internal voice - a picky voice.
The audience for a picky voice can be varied and can involve any subject matter, from picking a candidate for the city council to a common food product in a supermarket. There's always quite a number of people in the target audience that are bound to be picky and are going to have a stronger connection with a voice that sounds like their internal picky self.
A picky voice usually speaks very slow, like it is counting every syllable in every word it utters, as if if it is sorting arguments pro and con. Its pich can be either high or low, but alwys rolling out words with meaning and a pace that makes the listener/viewer digest the arguments presented.