INSURANCE ALWAYS REJECTS MY CLAIMS

I have logged 3 faults, and all were declined citing the event not covered under insurance, this outcome would be based on an assessment by a service provider appointed by the insurer, One was for damages to my cupboards due to suspicious leak in my wall. This was declined as they said poor workmanship on the unit and I have has these cupboards for years with no issues. Without the leak there wouldn't have been an issue. Then I logged a call for the leak, then I was informed they dont cover that I will have to take care of it my self. Recently logged a call for assessment of damages after underground pipe leak, I was informed AGAIN that the insurance does not cover this and i will have to sort it out myself as the crack in my wall in poor workmanship I find this very insulting. My question then is what does it cover because it feels like I am paying for something that I will always be rejected when I need it the most. Where is the sense of security in this when you have 95% chance of a rejection ...I am highly disappointed.