Comercials are very stiky because they talk about the same thing always. Their only pourpouse is to convince people to buy their product. They make this by creating a small stiky song, repeating over and over what they product is capable of, or putting it in offer and giving free things that will come along with the product. Some other comercials try to create an impression on you so you can start making conscience about a problem the world is facing. The comercials I've watch so far are really effective. They really make me think about things that are going on around us and no one seems to notice. For example, the comercials of Dove talk about the girl's self-steem, how girls are not comfortable with the body they have and how they wish they could be blond, or brunette or skiny. They also think they're ugly so they decide to cover their real face with make up and create a fake person using fotoshop.
In my comercial I´ll try to convince people about something. It could be quit somking, use protection while having sex, or love theirselves, their body, what they were given and have.