If you're starting a new relationship, you might wonder if you'll end up being compatible or not. Of course, you don't want to waste each other's time, so it's a good idea to figure things out ASAP, in a casual way. You might not experience all of these issues early on, which can cause you to strengthen the relationship on the surface level, but as you do start to have the "big talk" and open up discussion for serious matters that could affect the long term, you'll begin to determine whether or not this relationship has real potential for lasting success. Hopefully, it does! Here are a few subject matters that can cause controversy in a relationship - as in, if you don't agree, it could cause obstacles moving forward.