@archer Very few return from UK to their country of origin. Those granted some form of status (after going through multiple processes, about 50 percent get granted) invariably stay long term. Single people often apply for family reunion (eg i know lots of Sudanese men who have been granted and then bring their family over). Vast majority end up working and contributing. However, refugees based in refugee camps in neighbouring countries often return.
The whole thing is very complex. For example, a big problem is how to get refused asylum seekers back to their country of origin when: the UK gov may have refused their claim because the claiment cannot prove they are from the country they say they are from (human trafficers usually steal passports): UK gov may not have an embassy in that country (makes returning dificult): UK gov can only return if there is a safe viable route. And fact is, why would they want to go back – a life working illegally in UK is usually more appealling than going back to a shit country.