Ever feel trapped in a never-ending conversation? Well, you’re not the only one, according to a new study. A group of researchers surveyed over 800 people and found conversations almost never end when both parties want them to – and people don’t really think about their partner’s desires to end the conversation.

Back when he was studying for his master’s degree at the University of Oxford, Adam Mastroianni used to attend black-tie events and wonder how many people were stuck in conversations they couldn’t get out of. “What if we’re all trapped in conversations because we mistakenly think the other person wants to continue?” he asked himself.

It’s probably happened to all of us at some point. You’re not really into the conversation, but you don’t want to be rude so you half-heartedly keep going. Turns out, it’s very common.

Most previous studies about conversations were done by linguistics or sociologists. Psychologists did look at conversations but only as a way to study other things, such as how people use words to persuade. A few studies have explored the phrases used by individuals at the end of conversations, but not focusing on when people choose to say them.

“People feel like it’s a social rupture to say: ‘I’m ready to go’, or to say: ‘I want to keep going although I feel like you don’t want to keep going.’ Because of that, we’re pretty skilled at not broadcasting that information,” Mastroianni told New Scientist. “Whatever you think the other person wants, you may well be wrong. So you might as well leave at the first time it seemed appropriate.”

Now a Ph.D. student in Psychology, Mastroianni wanted to get some answers. With a group of researchers, he surveyed over 800 people randomly recruited from a crowdsourcing marketplace website. Participants responded to questions about recent conservations they had, including how they felt about the length and the way the conversation ended.

The researchers also worked with more than 250 students and non-students pooled from volunteers available for studies in the Harvard University psychology department. The group participated in one-on-one conversations with another participant, who they didn’t already know. They could chat for as long as they wanted, up to a maximum of 45 minutes.

When they finished talking, both study participants could leave the room and each was quizzed about the conversation. If the conversation lasted 45 minutes, one of the researchers stepped into the room to end it. Most of the pairs engaged in chitchat about where they grew up or what they were studying. It was mostly boring, even “hard to watch them,” Mastroianni recalls.

The findings showed most of the conversations rarely ended when people wanted to, even when both participants wanted to stop. The length of the conversations was off by about 50% compared with how long people would have liked them to last. Only 10% of the participants ended the conversations even though both people wanted to continue.

“They could have kept going; they had time left. But for some reason they stopped, maybe thinking they were doing a nice thing by letting the other person go,” Mastroianni said. People in conversations want different endpoints and know very little about what their partners actually want. But this doesn’t mean they don’t enjoy the conversations, he added.

Thalia Wheatley, a social psychologist at Dartmouth College, who was not involved in the study, told Scientific American it was “astounding” to find out people fail so much in judging when a conversation partner wisher to wrap things up. Conversations are otherwise “such an elegant expression of mutual coordination,” she said. “And yet it all falls apart at the end because we just can’t figure out when to stop.”

The researchers only covered people from the United States, which raises the question of whether the rules of conversations are clearer in other cultures or not. The study was published in the journal PNAS.