Many years back a CEO of a subdivision of a company wanted to know why his email service was disrupted. I told them that it was because their idiot webmaster took control of their DNS and did not copy the MX record. The webmaster defended himself claiming that a document was not in place explaining how to handle the client's DNS. This went back and forth a bit between the three of us, and ended with me calling the two of them incompetent and irresponsible. I never spoke to the webmaster or the client CEO for better or worse.
A few years later, the CEO of the parent company called wanting to know why his network was suffering intermittent downtime and demanded it be fixed immediately. I explained that his outage was caused by antiquated equipment that could not do debugging, and there was a proposal already on his desk for replacement gear. He was in a huff, but he knew I didn't mince words or advice, and that quote was signed in minutes.
While you can't always directly point to a net gain after a net loss, your experience and attitude will help define how other perceive you. You can go in quite politely, or you can be very blunt. I have been both depending on the situation.
Either way, if you can't call out losers, you'll wind up being one.