The most common and most likely answer to this crossword clue is the 9 letter word TORTOISES
I've seen this crossword clue in The Daily Telegraph
T
O
R
T
O
I
S
E
S
Buddy explains!
The straight part
We know that "those who never 14" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case those who never 14 = tortoises.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does TORTOISES mean?
TORTOISES noun- Any of various land-dwelling reptiles, of the family Testudinidae or the order Testudines , whose body is enclosed in a shell (carapace plus plastron). The animal can withdraw its head and four legs partially into the shell, providing some protection from predators.