Say your Market Research Company was chosen to create a marketing strategy for a new “breakfast on the go” sandwich. In this case, it would be best to create a market research survey first. You definitely want to understand the benefits of why they would need "breakfast on the go."
For this type of survey not every person will do. You would need to qualify your recipients a bit and talk to people who would fit the target demographic -- in this case, college students and commuters. You want to make sure that you are getting the right questions to the right people. Target the individuals that will eventually buy this product.