Many things can be understood about the state of a relationship from the types of arguments it has. While it is normal to argue with any person in your life, it is important to note how the fight progresses, so that you know whether your relationship is healthy or not. If fights quickly transition into ultimatums (from one or both sides in the argument), that means that things are definitely toxic.
The reason why ultimatums don't work and are in fact a bad thing to do to your partner is that they don't solve the root cause of the problems in the relationship. Giving an ultimatum to someone is just a way to end the fight - not to deal with the problem. Even if the other person agrees to the ultimatum, they won't do it because they want to, but because they were forced to. Meaning, eventually things are going to revert back to how they were.