Why was my US B2 visa rejected? [closed]

I applied for a US B2 visa with family (wife and 2 children), from Saudi Arabia. I hold a Pakistani passport. My case goes like this:

I submitted an employment certificate stating my per annum basic salary, 32,000 dollars with other benefits, a bank statement with almost 13,000 dollars in the account.

The officer disqualified me on account of that it doesn’t make sense that one can spend half of the yearly salary on their vacations. He barely asked me two questions about why I want to visit and where I will go in the US.

I have travelled to the UK, Europe and other places, and have a good traveling history. I mentioned three weeks of stay and 3 cities to visit. Where did I go wrong?