Compatibility readings are least useful as a verdict and most useful as a translation.
Most couples who book a compatibility reading are not asking whether they should be together. They are asking why the same argument keeps arriving in the same shape. Two charts side by side answer that surprisingly well.
Conflict style is usually the clearest signal. One person processes stress by talking immediately; the other needs a day of silence before language is even possible. Neither is avoidance and neither is aggression, but each reads the other that way in the moment.
We also look at what each person treats as security. For one it may be routine and financial predictability; for the other, novelty and freedom of movement. Fights about holidays or spending are rarely about holidays or spending.
What a reading gives you is vocabulary you can use at 11pm on a bad night: this is my Moon doing what it does, this is yours doing something different. Naming the mechanism is not the same as excusing behaviour, but it does stop the argument from being about whether one of you is defective.