"You have no right to stay in the UK so are liable to be removed. You must leave the UK as soon as possible. If you do not leave voluntarily you may be prosecuted for an offence under theImmigration Act 1971 , the penalty for which is a fine of up to£2,500 and or up to 6 months' imprisonment and you will also be liable for removal from the UK."
"... perhaps the rather different one of deterring people from coming to this country in the first place without having obtained entry clearance and to do so by subjecting those who do come to the very substantial disruption of their lives involved in returning them abroad?"