Any number of factors can cause an attempted marriage to fail. Impaired consent is one major one. Unwillingness to have children is another. Even entering marri

Any number of factors can cause an attempted marriage to fail. Impaired consent is one major one. Unwillingness to have children is another. Even entering marriage with the expectation that divorce is possible means no sacramental marriage was formed. I suppose one can choose to view those factors as loopholes and I imagine some poorly formed Catholics do just that. That said, a validly celebrated marriage cannot be annulled. Whether or not tribunals are erroneously issuing declarations of nullity is a question I don’t know the answer to. In any event a Catholic who tries to game the system this way would be well advised to consider that God won’t be fooled.