Is successful (8)
(Other definitions for succeeds that I've seen before include "wins" , "turns out well" , "Follows on the throne and accomplishes what is attempted" , "Takes someone else's place" , "Reaches a desired goal" .)
'is successful' is the definition.
(I've seen this before)
This is all the clue.
(Another definition for does well that I've seen is " is successful".)