Ever since we've had cruise ship tourism in Croatia, Korčula has been one of the hot-spots.
Love it or hate it, cruise ship tourism is an important part of the industry, and for over a decade now it has been important for Korčulan tourism as well. Each year, restaurants and souvenir shops and even just people living in Korčula know when a large cruise ship is coming to Korčula, as those days are characterised by increased number of tourists walking around, shopping for souvenirs and sitting down in restaurants.
One of the lists I found online is here: http://crew-center.com/korcula-croatia-cruise-ship-schedule-2018, but I'm sure that there are many other cruise ships coming to Korčula this year, as I remember much more coming in 2017 than there are on their 2017 list.
And that's not even counting the smaller cruisers, coming each day to Korčula, docked one to the other, as many as 5 or 6 in a row, on the eastern Korčula port, and you won't be miss those as well.
But, sometimes your view of Korčula town will be improved by a set of a large cruise ship masts in the background!