If you ever had the misfortune to grapple with visa applications to Britain you may be interested in a report from the independent monitor of UK visas.
According to the report, common reasons for visa refusals include that applicants "plan a holiday for no particular purpose other than sightseeing" and lack "sufficient command of the language for the purposes of tourism".
The first point seems to be causing the most contention, not least because the official "Visit England" website seems to almost exclusively deal with how much fun you can have sightseeing here.
When it comes to command of the English language, the report offers an example of how applicants are informed that they have been refused: "The provenance of the funds depicted is not evidenced allied to other financial commitments. You have failed to complete pivotal areas of Section 6. I can only assess your mutual knowledge in a subjective context."
The report was commissioned by the Foreign Office.