It's unusual for misers to be careless (6)
I believe the answer is:
remiss
'be careless' is the definition.
(I've seen this before)
'it's unusual for misers' is the wordplay.
'misers' can be anagrammed to 'REMISS'.
Though, I am not clear how this is indicated.
'to' acts as a link.
Can you help me to learn more?
(Other definitions for remiss that I've seen before include "Lacking attention to duty" , "Negligent, lax" , "Wrong" , "delinquent" , "Not taking care" .)