There was a reason. However -- here is something Jesus said about the days of Noah when the Flood came, likening it to his return (not physical return though): You will find this in Matthew chapter 24:
"No one knows about that day or hour, not even the angels in heaven, nor the Son, but only the Father.
37As it was in the days of Noah, so will it be at the coming of the Son of Man.
38For in the days before the flood, people were eating and drinking, marrying and giving in marriage, up to the day Noah entered the ark.
39And they were oblivious, until the flood came and swept them all away. So will it be at the coming of the Son of Man.
40Two men will be in the field: one will be taken and the other left.
41Two women will be grinding at the mill: one will be taken and the other left."