It’s good to be nice–most of the time. But sometimes, researchers at the University of Arizona have found, being nice is a bad idea. Their study suggests that while making sacrifices in a romantic relationship is generally a positive thing, doing so on days when you are feeling stressed may not be beneficial. The researchers studied 164 couples, married and unmarried, whose relationships ranged in length from six months to 44 years. The participants provided daily reports, over the course of seven days, describing the sacrifices they made for their partner in 12 categories, such as child care, household tasks and amount of time spent with friends, among others. They also were asked to report on the number of hassles they experienced that day and how much those hassles affected them. The participants then ranked, on a scale of one to seven, how committed they felt to their partners, how close they felt to their partners and how satisfied they felt with their relationship that day. The good news? Those who made sacrifices for their significant others generally reported feeling more committed to their partners when they performed those nice behaviors. The less good news? When they made sacrifices on days when they had experienced a lot of hassles, they did not feel more committed. Read more from the University of Arizona.