Do you think birth control can fail

I know some people (adults) who have conceived their bundles of joy even though they were preventing. They love their children but of course it was shocking to them. Even more so, their families don't seem to have anything nice to say. They automatically pull the," Why didn't you use protection!" Or "You must have not used it right!" "Condoms aren't good enough, they break!" And fuss at them most of the pregnancy. I know the only 100% method is abstinence. Do these people really think birth control is a fail safe? Have you ever experienced this?