That's anecdotal at best. I highly doubt that the ratio is any more than 60/40 one way or the other. Usually it's ridiculous terms from both sides and an inability to settle for anything more than complete and total victory. See the Sirion war against Oligarch, where until Greater Xavax nobles joined there was literally no way that Sirion would have the forces to break Oligarch. Yet they refused to settle for anything but the destruction of Oligarch.
The players of this game on both sides of any war generally have little sense of what is a sensible negotiation.
Anecdotal? I'd place it between 80% and 95% of realm deaths due the losing realms digging their own graves, at least 75% due to the dying realms refusing reasonable offers being made to them, the rest dying because they did their best to make their enemies utterly despise them.
People are proud. They'd rather keep their OOC pride than keep some virtual holdings. A lot of things RL people would be delighted to accept as surrender conditions would just never be considered by BM players for this very reason.
