The Peter Principle states that a person will be promoted in an organization until they reach the point that they are too incompetent to perform their job duties. Parallels can be drawn to your personal relationships.
Too often we rush through the getting-to-know-you phase and the dating phase simply to be in the long-term-commitment phase. This is a big mistake. We’re promoting men to boyfriend status without them deserving it or proving that they’re capable of handling it. Then, once they’re at boyfriend status, they invariably fail. This isn’t always their fault – we’re giving them too much, too soon without requiring them to fulfill progressive steps (hint: they’re called progressive for a reason).
How do you solve this? First, take your foot off the gas. There are no prizes for getting to boyfriend status the fastest. Second, get to know him well, very well, so that you’re (fairly) certain you know what he’s capable of accomplishing. Lastly, make the relationship a series of progressive steps – don’t skip steps (you wouldn’t promote someone from file clerk to CEO in one fell swoop, would you?).