Life has stages. Sometimes, you desire a stage that is not in the present.
Being a teenager leaves you with a wish of becoming an adult. Being an adult leaves you with responsibilities and expectations that makes you wish you were still in your teen age. Being aged leaves you with the thought of starting afresh to plan your life all over again for mistakes you feel you wouldn't have made if a second chance of starting all over again is granted.

How vanity life would eventually become with no hope of eternity!!