I always do the $20 withdrawal in Aus a few days before leaving now, otherwise the card sits in the drawer.In Japan last October my card was declined due to 'inactivity'. I complained to Citibank about this as they had accepted deposits to the account prior to departure, and I hadn't been told the account was inactive. I couldn't see anything in the monthly statement emails that advised that the account was inactive.
Visited again last month and had no trouble withdrawing cash at an ATM in the hotel lobby (excellent rate and no fee). I had done a test withdrawal of $20 prior to leaving Australia, and will always make sure I do this prior to any future travels.