Every human being has a natural progression of planetary cycles affecting them as they grow.
1) MOON (Birth – 1) – they develop their emotional senses and are attached to their mother
2) MARS (1-3) – they first become their own independent person and start following their interests and passions around, learning to move on their own and walk to get to what they desire. Quite accident prone.
3) MERCURY (3-12) – the planet of the intellect governs the maturity through the most important ages of primary learning and education
4) VENUS (12-32) – Puberty. This is the most physically beautiful time of life (12-32), thus the maturity through this period is governed by the most beautiful and healthy planet, Venus. Marriage usually happens in this period as well.
5) JUPITER (32-50) – At this stage Jupiter should make us mature in the sense of having achieved some career success and thus have financial abundance and to start developing better sense of morality and philosophy about life.
6) SUN (50-70) – This is when the full maturity and power of a human being should come out. We should really be shining in this period as a result of all our experience and learning throughout our life so far.
7) SATURN (70-100) – This is when maturity inevitably causes severe gradual breakdown in our physical selves and we need to become wise, detached, and realistic about death.
You will find that persons with significant weaknesses to the above planets in their birth charts will not mature properly in maturity area/ages governed by that planet. Visa versa, excellent planets in the chart will have excellent maturity in their areas and ages.