When it comes to relationships, no matter the kind of relationships they are, there really aren't any guarantees. Breakups are always a possibility with romantic partners or friends, people lose touch, things happen. And, of course, while you often make a serious commitment to staying together long-term when you get married, even those kinds of relationships don't offer any certainty. Separations and divorces are a potential endpoint here too. And if these things are true about your partner before marriage, you're twice as likely to get divorced.
Of course, just because there are things that can raise your risk of getting divorced (even double or more), there are still no guarantees that things will end that way. Risk factors don't mean that you'll definitely end up divorced, it just means that you might be more likely to. There are many more factors that influence whether or not your marriage will make it long-term — personality traits and life circumstances aren't the absolute deciding factors. That being said, it can be interesting to look at some of the things that might affect whether or not your marriage is ultimately successful so that you know what sorts of added risk factors might apply in your specific case.
So though these are just risk factors, because they could make it twice as likely that your marriage will end in divorce, it might be worth taking a closer look.