With boards, size does matter. Many organizations add members to their boards in order to have greater expertise or view points. However, here is an anecdote that shows what can happen when a board is too large.
About 10 years ago, a board that I represented met in December to consider the compensation of the organization's CEO for the next year. The board had 43 members, of which 24 were in attendance at the December meeting. A large plurality of those 24 in attendance approved the compensation recommended by the board's compensation committee.
At the following January meeting, a different combination of 26 of the 43 members was in attendance. A majority of those 26 members refused to adopt the minutes of the December meeting that had approved the CEO's compensation. The members present at the January meeting voted to reconsider the CEO's compensation at the March meeting. It took until the May meeting to resolve the compensation issue.
Although "words" are the focus of my professional life now, statistics used to be. In a prior life I dealt with probabilities, predicting, for example, who would be elected Senator of Illinois or whether consumers favor Gillette razor blades over Schick.
For a board of 43 members, there are approximately one trillion different combinations of members that may constitute a majority. So, statistically, we should not be surprised when a board of 43 reverses itself from meeting to meeting.
For a board of 20 members, there are 167,960 possible combinations of members that may constitute a majority. Still a large number, but less than a trillion.
Industrial psychologists generally believe that an ideal board size for making decisions after full discussion is 11 members. For a board of 11, there are only 462 combinations of members that may constitute a majority. This provides much more certainty than a board of 20 or 43 members.
I have found that boards of eight or nine members work well. A board of eight, being an even number, uniquely requires five of the eight to constitute a majority, and for a board of eight, there are only 56 possible combinations of members that may constitute a plurality of five. For a board of nine, there are 126 possible combinations of members that may constitute a majority.
Larger boards are typically found at non-profit organizations where one of the responsibilities of its members is to solicite charitable donations. In recent years, many organizations have delegated the solicitation responsibility to a separate foundation having a board composed of members believed to have some ability to make or solicit donations. Others have created an executive committee composed of some, but not all, of the board members to consider and approve matters requiring some certainty, such as approval of compensation or materials contracts.
With boards, size does matter. The ideal board has enough members with differing expertise and experience to give it the diversity of both thought and expertise to oversee the direction of the organization. At the same time, it is not so large as to result in deviations in that oversight from meeting to meeting depending upon who is in attendance.