Good question - I recently was researching monasteries I might visit and read this http://www.bhavanasociety.org/main/page ... n_process/
Their requirements for ordination are that you be between 25-35 - I'm to old
this is a little off the ordination subject but I read this and it left me scratching my head - from:The Requisites of Enlightenment by Venerable Ledi Sayādaw
To put it in context he's speaking of the Four Types of Capacity for Path Attainment
"Further classes also arise, as for example in the case of individuals whose necessary period of practice is
seven days; the stage of an arahat may be attained if effort is made in the first or second period of life,3 while
no more than the lower stages of the paths and the fruits can be attained if effort be made only in the third
period of life."
2This is not mentioned in the canonical texts referred to above, and their commentaries. (Editor)
3Three periods of life are usually distinguished, viz. youth, middle, and old age. See Path of Purification
(Visuddhimagga), tr. by Bhikkhu Ñāṇamoli, p. 721.
He seems to be saying in the last line that if your of a certain age you won't reach Arahant stage ? I think there' is or maybe was some emphasis on age in the past because the path isn't easy - anyhow just a thought