I am of the same opinion - trying to put down reasons based on what was mentioned earlier.No, that is the conclusion, but what is the explanation ? you need to request the officer's notes so that you can determine what evidence was lacking on your part that you can present to the tribunal.
Did you have an interview?
1. If you were married before - was it document that you legally eligible for your next marriage ( before you application )- you had your divorce documented.
2. Was it that you had some inconsistency in your interview of the applicant vs what was in application.
I am just trying to assume and support , it’s very important friend to know the cause and provide the reason. Preparation is the key.
Do you have a lawyer to support you.