Interestingly enough in Warws of Reaving that log from one Star Adder scientist states that ambition is usually curbed at the first sign of manifestation. Then what is "good" aqmbition and what is actually "bad" ambition? Would that be sacrificing your star mates to achieve victory? Or winning by underhanded means? And even that is debatable as clan culture has proven to be quite hypocritical.
Are you talking about ambition amongst the Scientists? I think that's what they were getting at. The lines in Wars of Reaving from the scientist perspective usually are trying to address how the scientists saw their efforts as being chained and confined. I remember one line from that book from a scientist that was like "Scientist? Bah we haven't been allowed to be scientists for a long time now."
He was talking about the ability to do pure research for research's sake. To do it purely for that act of scientific discovery.
It's an attempt to shed light on the scientist perspective, why they did what they did. Why the Society existed.
What they meant was, the warriors dictate priorities and control what they do and can't do. The warriors decides the research priorities and tilt the scientists toward better weapons, better genetics. "Scientific research purely for the sake of humanity" was probably NOT a research priority. The scientists found this frustrating at times and then were absolutely horrified by IlKhan Brett Andrews' reaving decree, which stood to undo generations of their work.
But that's the scientist caste. The warriors are a different caste with a different lifestyle where ambition is encouraged. You fight to get a bloodname, you fight for higher rank. But ambition doesn't have to be individual, ambition can be a team sport. Team meaning your unit, including your subordinates.
The most successful Clan warriors build a coalition. A coalition of supporters within their commands, a coalition in the Clan Council. With a lot of supporters, they have an easier time rising to better positions/ranks.Clan commanders do look at situations and evaluate what acceptable risks and acceptable losses are. If you are achieving victory but always at an unacceptable rate of loss for warriors and equipment, you stand a decent risk of being challenged for it. Of being demoted, challenged for their rank and position or to a Trial of Greviance by one of the survivors who think you threw all their trothkin away for bad reasons. Challenged by an up-and-comer who thinks they can do better and wants your rank and position.
The Clan Way means it's easier to deal with bad leaders and bad warriors. Even if that bad leader defeats a challenger, that may only buy them a little time before the next challenger comes along. If nothing else that bad leader or bad warrior becomes unpopular, and while its not emphasized as much, yes, being a successful Clan warrior is a bit of popularity contest. Meaning those who make too many enemies and not enough friends (a coalition) have a hard time rising.
The most demonstrated example of this that we have is politics. Wardens supporting other Wardens, Crusaders supporting other Crusaders, that kind of thing. For example Trent noted that becoming a Warden in the Smoke Jaguars (a practically all-Crusader Clan) would kill his career and probably see his life cut short.
We've also seen lots of situations where the ranking Clan warriors have shared history. Where a Galaxy Commander and the Khan once served together. Or where a Senior Clan officer's politics happen to align with those of the Khan. It's not uncommon to notice that the warriors who are ultimately very successful, then elevate their supporters and coalition members.
Those very successful warriors don't trample all over their coalition to elevate themselves, their supporters help to elevate them, and then they return the favor. The very successful Clan warriors are 1. Excellent individual warriors who tend to win individual battles, 2. Excellent leaders who tend to lead their warriors to victory with acceptable losses of equipment and warriors, and 3. Popular in the Clan Council, whether that means they are leading a coalition of their fellow warriors, or are a member of a Coalition of fellow warriors.
So if you have a habit of making enemies everywhere you go, and develop a bad reputation as a warrior who just gets other warriors killed for sake of their own ambition, it's hard to rise very far because you are doing it purely alone and with challengers coming your way around every corner.
