Solving donation coordination problems

In a comment on GWWC’s recent fundraising appeal, I asked whether prospective donors were holding off on donating until the end of the fundraiser, out of the worry that it would hit its goal early and thus their donation would not have any counterfactual impact. About 50% of people who answered the poll said that they were influenced “at least in part” by this reasoning.

So it sounds like we might have a coordination problem on our hands that causes everyone to wait until the last minute to donate to large fundraisers. Unfortunately, as Rob Wiblin notes, this

comes at the cost that we have to put in more time—perhaps a month of staff time—in order to eventually reach our goal. In addition, there’s the stress and uncertainty it creates for us.

So it seems like it might be useful to figure out a more efficient way of allocating EA donations that didn’t waste so much org time by donors waiting until the last minute. What are people’s thoughts on how we could accomplish this?