Since we were on part of a world cruise it gave me an opportunity to evaluate the merits of these since this got me to focusing on the merits and dismerits of booking the entire package if we had chosen to do so. We have never booked a "world cruise". Our longest cruise was one just shy of three months, which was 95% Africa ports. Most likely the reason we haven't booked longer voyages is that by now we have visited just about every port offered on those, many, multiple times. My advice to those just beginning cruising careers, if they can make it work, take a world cruise as soon as you can, that way most ports on the itinerary will involve first visits making the voyage that much more enjoyable.
I did note on this voyage over 80% of the guests were taking the entire 111 day world voyage and out of those there were a lot who love to do this time and time again regardless of the number of visits they may have had at the same ports. We met couples that have been on more than five and often they were friends with others that had been on the same voyages. Camaraderie was a big inducement factor. Obviously, cruising is not the same for all, there are many types and variations. However, we see now the world cruise probably isn't for us.
We do love sea days and you do get a lot of those on world cruises, which is a plus for us. But It seems to me that the industry is rather coy in describing "world cruises" or "world voyages" as these are somewhat misnomers. The one we were just involved in was indeed a cruise that went all the way around the globe, beginning and ending in Florida. However, to call this a "world cruise" is rather disingenuous. 20 of the 47 ports are all in the Mediterranean, there is no Africa, no South America, no---Indonesia, Asia, Malaysia, Baltic, British Isles, Holy Land, Antarctica or Arctic or much more, most all of it is confined to traditional tourist haunts within the Northern Hemisphere, with the exception of a jaunt down the Pacific to Australia and then back north. One fellow, on his 5th world cruise, told me he was "bored". My preference now would be to get more bang for my buck by booking separate cruises of four or five week durations each, maybe lumping two together as a back to back (B2B).