Oyster refunds
 

I can't make sense of the TfL website on refunds of unused credit on
Oyster cards. At one point it states: 'You might be able to get
unused pay as you go credit, Travelcards or Bus & Tram Passes refunded
if you don't need them anymore.'

I'm wondering what happens with tourists. I see there is a Visitor
Oyster card pre-loaded with credit but what happens when the visit
ends? Can the tourist get unused credit refunded? And also, can the
cards be reused (recycled) or is a new card needed each time?