To show in the bible that the wicked has no future at all, one calamity is enough to destroy him with no hope of recovery.
How many times GOD will help the righteous?
Seven symbolizes completeness in the bible. Any time the righteous fall, the LORD is always there to raise him up.
Proverbs 24:16 (Amplified Bible)
For a righteous man falls seven times and rises again, but the wicked are overthrown