The most common and most likely answer to this crossword clue is the 9 letter word REPROBATE
I've seen this crossword clue in Financial Times
R
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More clues leading to the result REPROBATE
- Agent with habit fed by volunteers turned rogue
- Soldiers will copy someone depraved
- Discount housing for criminal
- Villain concerned with what’s needed to get hold of legacy
- Rake in money coming back that expert divides
- Record loot hoarded by rank villain
- Villain concerned with investigation about a contract’s conclusion
- Degenerate salesman worried about rifle
- Unprincipled soldiers given test of will
- Put another way, bore apt to follow first signs of roguish excess?
Buddy explains!

The straight part
We know that "Put another way, bore apt to follow first signs of roguish excess" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case put another way, bore apt to follow first signs of roguish excess = reprobate.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does REPROBATE mean?
REPROBATE noun- One rejected by God; a sinful person.
- An individual with low morals or principles.
- Rejected; cast off as worthless.
- Rejected by God; damned, sinful.
- Immoral, having no religious or principled character.
- To have strong disapproval of something; to reprove; to condemn.
- Of God: to abandon or reject, to deny eternal bliss.
- To refuse, set aside.