This is a tactic used to qualify the person negotiating as having some virtue. This is a big tell that the speaker is the opposite of what they claim to be, and often works on novices. We may even do it ourselves when we feel we like a deal is slipping away and we think there is some objection to ourselves as to why it won’t close, because we mistakenly tend to think it is all about us. As Fisher and Ury say in Getting to Yes, get the people out of the deal and focus on the problem. Nervousness shines brightly when defensive qualifiers are introduced; they can highlight a lack of belief in one’s position. Be very wary if you hear defensive words – do they think you can’t trust them, or should you not trust them?