For some interviews or meetings, making notes (or taking Minutes) is fine, however, there are certain times when having an audio recording would be far more beneficial. It ensures accuracy and, should the need arise, it can be used to ascertain exactly who said what.
Recording an interview, meeting, focus group or brain-storming session (from this point forward I will use "meeting" to represent all of these) is a great way to ensure you have an accurate record of everything that was said by the participants. However, you need to do more that just stick the microphone on the table. A little forethought will make the difference between being able to hear every word or people were too quiet or drowned out by background noise, especially if you're planning to do a transcript of the recording.