Does your group have an official minute taker?
Minutes are an important part of every meeting as they form the official record of what has actually happened and what the board has agreed to do. For some groups the decision about who is taking minutes is made at the start of each meeting based on who showed up! This means that the minute taker is chosen from the directors.
I have recently seen information that indicates the person taking minutes should not be participating in the meeting. What is your policy about that?
If you are asking a regular board member to take the minutes, then you are reducing the amount of interaction that board member can have in the meeting as they will be busy with the minute taking. The other possibility is that the minute taker is participating in the discussion and not taking the minutes. Either one of these situations can present problems.
Maybe your board should consider having a minute taker who is not on the board. This person would be able to improve on their minute taking abilities by getting lots of practice. When different people take the minutes each meeting there is likely no consistent style and maybe no one gets good at it!