Keeping a marriage afloat can feel complicated and difficult for many couples. In the United States, about 40 to 50 percent of marriages end in divorce, while 57 percent of men admit to committing infidelity in any relationship they’ve had, and 74 percent of men admit they’d have an affair if they knew they wouldn’t get caught.

“Men don’t leave. They just want it all,” says an article published in Today, in which several women who have relationships with married men comment on how these men “never” leave their wives. Although this does not apply in all cases, it is very common for men not to leave their wives for their lovers. But why?

1. He can be himself
He has known you forever, and no one else knows him as he really is. You give him the opportunity to be authentic, because there’s no part of him you haven’t seen before. With you he, he is comfortable.

“Why would he leave his wife and kids?” says David Wygant from Your Tango, explaining how after being with their girlfriends, cheating husbands then get to back home to play with his kids and have his wife take care of his home. “It’s the ideal situation for a guy.”