Three is a magic number in writing, and can help you craft stronger stories.
There was a joke in my house growing up, that things always happened in threes—good luck, bad luck, it didn't matter. If the car broke down, that meant two other things were sure to break within a few weeks. Someone got a raise, well, then two more good things were certainly on the way.
Most of the time it did actually happen—but probably not for the reasons you'd think. Good and bad things happen all the time, but we don't always notice them or make the connection to other similar events. It’s part of our culture and so ingrained in our subconscious that we notice (if not seek out) patterns that fit this rule.