Put off before I make a speech and go off (11)

I believe the answer is:

deteriorate

I'm a little stuck... Click here to teach me more about this clue!

'go off' is the definition.
'deteriorate' can be an answer for 'go' (thesaurus). I am unsure of the 'off' bit.

'put off before i make a speech' is the wordplay.
'put off' becomes 'deter' (both can mean to discourage).
'before' means one lot of letters go next to another.
'make a speech' becomes 'orate' (I've seen this in another clue).
'deter'+'i'+'orate'='DETERIORATE'

'and' acts as a link.

Can you help me to learn more?

(Other definitions for deteriorate that I've seen before include "Become steadily worse" , "Become progressively worse" , "Slip" , "Fail" , "Gradually worsen" .)

I've seen this clue in The Globe and Mail.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.