Beauty spots are just moles on the face. There is no way of controlling when, where or whether they will turn up! Some people are born with them and others develop moles as they get older, particularly if they go in the sun a lot. Moles are fairly harmless, but if they change shape, bleed or change colour then it is important to see a doctor as this might be a sign of skin cancer.
Moles have been considered to represent beauty for a long time, actresses and models such as Cindy Crawford or Marilyn Monroe very famously had moles on their faces and it was thought these made them more beautiful. Personally, I quite like moles as they are a bit different.