Launching a new product/Introducing a new brand takes focused research and strategic planning. You must first understand the market and 'learn' the people you want to reach. Therefore, you should 'listen' before taking any communicative action.
But don't think 'listening' should only be done before launching or introducing a new brand. Make 'listening' part of your everyday strategy. Meaning that, your customers will always share what they want and what they are looking for. It's your job (and your team's job) to always listen to them before taking any action, since every action done outwardly is "for" them. Correct?
After all, they are the ones that will make or break your brand by their actions of buying or not buying. So consider them when speaking to them.
Moral of the story?
In marketing (and in life):
Take the time to listen and learn before speaking.