How 'less beneficial' does it have to be before it's on net a better idea to just stay in Syria, or Eritrea, or wherever?
According to EU figures, 220,000 irregular migrants reached Italy and Greece last year, and the numbers have surpassed that this year. Of the total, around 40% were Syrians and Eritreans fleeing war and oppression with very good chances of lodging successful asylum claims in the EU.
Britain is not set to take any of the 40,000 as it is exempted from EU asylum policy unless it wants to take part.