In my experience working with "thousands" of refugee claiments I personally believe most were fraudulent, but their claims still needed to be heard to comply with the Convention. I've seen claiments from Ireland, Britain, Germany and the US. They still had to be considered by a delegated person.
In Australia most illegal non-citizens are removed, Deportation with a formal document is rare, usually just criminals who were on PR. I spent a time running a Criminal Deportations branch. A Minister, fed up with all the avenues of appeal, later decided to expel these people using character legislation, On forums like this posters generally believe all removals are deportations. Easier to not correct.