Make time to fail (6)
I believe the answer is:
forget
'to fail' is the definition.
(synonyms)
'make time' is the wordplay.
I cannot really understand how this works, but
'make' could be 'forge' (forging is a kind of making) and 'forge' is present in the answer.
'time' could be 't' (abbreviation) and 't' is present in the answer.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for forget that I've seen before include "Neglect (to do)" , "Don't remember" , "Leave behind unintentionally" , "Stop thinking about" , "Be unable to remember" .)