Number of 40 --Genesis 7

What does 40 mean?
The flood came upon the earth for 40 days, Jesus fasted for 40 days, Moses went up the mountain for 40 days, the Israelites in the desert for 40 years, Moses' three 40s...

A completely new beginning, a big turn around, a new hope in the entire hopelessness, time for the desert, a season in God's timing, a new phase...