This is not really a convenience, more of a commentary shared by a convenience writer who appears to have been getting older and appears to have been feeling unheard or less valued.
This convenience writer acknowledges that the period between birth and middle age seems to be the most active and vigorous time of life, but asks that experience in older age be valued as well.
Convenience Comments About Age
Different seasons make very satisfactory conditions
Germination to October is the most vigorous interval
But experience should be more honored