At TransPerfect, our business model depends on developing strong managers, and we spend a lot of time coaching our future leaders. A key part of Management is managing expectations. As a general matter: anytime someone is upset or feels treated unfairly in business, it can probably be boiled down to that person expecting something and, later, that expectation going unmet. When you are dealing with clients, colleagues, vendors, or any stakeholder in the business, be sure not create an expectation that goes unmet. Like much of what TransPerfect coaches, this applies not only to business, but can apply to other aspects of life.