For example, the NHS would implode if it were not for Indian doctors and foreign nurses; and there would be no council houses at all, if poor Italian immigrants had not been brought to the UK by Harold MacMillan to make the bricks that Englishmen refused to make at the time.
Poles, and other Eastern Europeans, do jobs that the indigenous people in the UK do not want to do, and are incapable of doing as well (based on customer service, attitude, work-rate and productivity).
However, there are extra costs like housing, the need to build better infrastructure, more unemployment among the population here caused by employers preferring immigrants to people from here who have too unhealthy an interest in going on holiday and doing as little work as possible.
Note: UK worker productivity is 16% behind the average for the G7, and there are 47 potential workers for every position which affords UK employers a very wide choice.
Immigrants, like Roma gypsies, and those who deliberately do not learn English, have very large families, multiple wives and dependents, and choose not to work, or engage in crime, benefit fraud and malfeasance clearly represent a net cost to the country. They should be deported or not allowed to come here in the first place.
The UK Government does not know how to properly evaluate the net contribution that an individual immigrant or class of immigrants makes as these questionable figures show.
The UK public are similarly ignorant of the facts and have learned nothing from before the time I was born, but until the Government is prepared to confront them over their lack of productivity and the growing obesity that is one of the main causes of that lack of productivity, the UK will have to have immigrants.
There is a parallel for this.
People in Singapore complained about the number of foreign workers and maids living there. The Minister told them that they had a choice – do the less attractive and menial roles or accept the need for immigrants. Since that adult conversation, people in that successful country accepted what their Employment Minister said. Here, the public are not prepared for that sort of straight talking and the Government is still afraid to confront them or provide real figures that take ALL the factors into account.