Alternatively, life is such a struggle between man’s body and soul, that with so many years to live, a person is bound to succumb over time.
As a result, God decided to shorten man’s lifespan, making 120 years the new limit (Chizkuni, Abarbanel, Malbim, Ha’amek Davar, see also Talmud Chullin 139b and Midrash Ha Gadol).
The average person, knowing he had so many centuries to go, did not fear death and his ultimate encounter with God.
Bechaye, Sforno) understand that verse differently. The limit of 120 years was not a permanent decree on man’s lifespan, but a final deadline God had given mankind before his destruction.
If man would not repent within the next 120 years, the Flood would ensue.
The commentators explain that God’s decree of 120 years was a gradual one.
Man’s lifetime slowly decreased from 900 to 120 by Moses’s time.
And, although most bars in Britain serve their G&Ts in tall glasses, he believes that a large, wide glass – like the balloon glasses the drink is often served in in Spain - is actually the best way to appreciate the flavour.
“Eighty per cent of what you taste comes through your nose.
(In fact, Noah was commanded to begin construction of the ark a full 120 years in advance (and on top of a mountain) so that people would notice and inquire – and perhaps Noah’s response would stir them to repent in time.) A second possible source is Moses’s lifespan.
Moses lived till exactly 120 (Talmud Sotah 13b) – and on top of it the Torah attests that his energy and vitality did not diminish in the slightest before that time (Deut. We thus bless people today that they be granted the same long, productive life of our great teacher Moses.
Why, Moses’s own brother Aaron lived till 123, and our forefathers down to his time lived well upwards of 120.
In modern times, Jeanne Calment beat the limit by over 2 years.
I think it's becoming more of a necessity as these funds [such as the Canadian Television Fund] dry up.