Hi Scot,
You wrote:
Sue explained to me that the goal was to have WMF's budget be roughly 50%
grants and 50% user contributions to guard against unexpected fragility with either of these funding sources.
[...]
This was Sue's explanation. I don't know if this is still the explicit thinking of the current board/ED, but IMO it's still an entirely reasonable rationale for pursuing grant funding, even if the grants come with more "strings attached" than a banner campaign.
You raise a valid question: how many sources of funding does the Wikimedia Foundation need? The Bridgespan Group is a consultancy firm specialized in non-profits. They have been hired in the past by the Wikimedia Foundtion, for example in the period of strategy formation that led to the 2012-2015 Wikimedia strategy.
The Bridgespan Group has done extensive research in funding models. One of their researches in this area has lead to a publication in Spring 2007 "How Nonprofits Get Really Big." [1] You might spell that publication word by word. At the bottom you find a link.
One of the parts in that report is titled "The Myth of Diversification." That title speaks for itself. The finding of the Bridgespan Group is that ''most of the organizations that have gotten really big [...] did so by concentrating on one type of funding source."
The banner fundraising campaigns by the Wikimedia Foundation are a perfectly mission aligned funding model for a non-profit. Somebody else might view the Wikimedia Foundation funding model as pay-as-you-want. [2] Some readers do and most readers do not donate a couple of bucks. However, that "Some readers" amounts to several million people who just love Wikipedia.
Please note that the Wikimedia Foundation was a "small" foundation back in 2007 when the Bridgespan Group conducted their research. The Wikimedia Foundation was not included in the list of 144 nonprofits, all founded after 1969, who were earning at least $50 million per year by 2003. Would the research be repeated today, the Wikimedia Foundation would end up in the top half of that list, and be a prime example of getting big as a non profit by concentrating on a single mission aligned funding source.
Regards,
Ad
[1] http://ssir.org/images/articles/2007SP_feature_fosterfine.pdf [2] https://en.wikipedia.org/wiki/Pay_what_you_want