Drive to succeed? No, I'm a bit stupid (8)
I believe the answer is:
ambition
'drive to succeed?' is the definition.
(I've seen this before)
'no i'm a bit stupid' is the wordplay.
'stupid' is an anagram indicator (in a stupid order).
'no'+'im'+'a'+'bit'='noimabit'
'noimabit' is an anagram of 'AMBITION'.
(Other definitions for ambition that I've seen before include "Strong drive for success" , "Desire for power, fame, etc" , "Aspiration, dream" , "Cherished aspiration" , "I'm in boat (anag.)" .)