Things unfold. Needs change.
We want them to unfold without unravelling.
Part of the problem with major giving at the outset is that people don't recognize the continuing need. On the smaller scale, it's like the great outpouring of support given to a family at a funeral, followed by group amnesia in the weeks that follow.
The survivors won't profit much from the gift of food in these beginning weeks if we leave them to a typhoid epidemic that sweeps through a tent city in the months that follow because we already "gave at the office" and are not inclined to remember to help in long-term recovery efforts.
I think that's what Larry was getting at.