"You haven't a clue as to why the people voted to leave, Teribus, because they were asked only if they wanted to leave or not, not why."

Oh Dear, wrong again!

Sovereignty

On the day of the referendum Lord Ashcroft's polling team questioned 12,369 people who had completed voting. This poll produced data that showed that 'Nearly half (49%) of leave voters said the biggest single reason for wanting to leave the European Union was "the principle that decisions about the UK should be taken in the UK".

Immediately prior to the vote, Ipsos MORI data showed that Europe was the third most highly ranked problem by Britons who were asked to name the most important issues facing the country, with 32% of respondents naming it as an issue.
Immigration

Lord Ashcroft's election day poll of 12,369 voters also discovered that 'One third (33%) [of leave voters] said the main reason was that leaving "offered the best chance for the UK to regain control over immigration and its own borders."'