He who hesitates, wins.

Normally you hear the phrase "He who hesitates looses," but in many fund raising scenarios that is not the case, instead "He who hesitates wins"

Recently I had asked for a sizeable gift and was very specific on the dollar amount. The person came back very quickly and agreed to give at a lower level. I was happy for the gift but deep down inside I wanted to get the bigger gift. I hesitated briefly and then the donor came back and agreed to do the very amount I had requested.