Excellent question.
The only explanation that comes to my mind is that they didn't want to pay overtime two nights in a row for the same raid. However, in the long run, I suspect this will cost them much more in both dollars and respect.
Hey, the informant called and said the lab is at 666 Swat Street. We just forgot to ask him (her) just where it WAS at 666 Swat St.
This is prolly going to end up with fingers pointing all over the place and nobody taking responsibility.