Even a city girl like me knows about "looking a gift horse in the mouth"-- it related to "getting long in the tooth"

Grazing animals (like horses) have teeth that grow forward not up-- so as the get older, their teeth get longer-- at some point they stop growing-- and just wear down.

You don't look a gift horse in the mouth, since to do so it to learn how old (and guess) how much usefull life it has left. We don't get old-- but at some point we decide that its time to stop reading serial novels...

as of the trojains-- they had Casandra-- and ignored her-- and failed to beware of greeks bearing gifts. (poor casandra-- her life didn't improve much after the war, did it?)