The EU is corrupt. It has failed to present accounts for goodness knows how long.
The EU is incompetent. Had the EU offered any kind of effective reform before the referendum we may not have voted to leave.
The EU is dishonest. When we last voted in the 70s it was about remaining in or leaving an economic community. The plan for political union existed then but was hidden. This was dishonest.
The EU is undemocratic. We were never allowed to vote on stuff they reckoned we would reject. We cannot elect any of the people who originate policy.
The EU is a train wreck in the process of happening.

We are seriously well off outside of it.