Through quantitative market research you can glean reliable facts and statistics which you can use to make informed business decisions. Think surveys and questionnaires with multiple choice answers and close-ended questions. To make it worthwhile, you need to have a large enough pool of respondents to gather data from. This then needs to be analysed and collated in a way that makes it easy for you to make those business decisions.
Not all small businesses have the capabilities or resources to turn the raw data into meaningful insights. In this case, qualitative market research can be more useful.