I turned out to be devoid of proven ability (7)
I believe the answer is:
untried
'be devoid of proven ability' is the definition.
I can't tell whether this definition defines the answer.
'i turned out' is the wordplay.
'out' indicates an anagram (out can mean wrong or inaccurate).
'i'+'turned'='iturned'
'iturned' with letters rearranged gives 'UNTRIED'.
'to' acts as a link.
Can you help me to learn more?
(Other definitions for untried that I've seen before include "virgin" , "inexperienced" , "Experimental" , "Intrude, being not yet tested" , "not yet proved reliable" .)