If the reasons I gave in my World of Diablo post against Diablo 3's online-only mode weren't enough, here are some more, that I've discovered over the past few days:
1) Weekly/server maintenance. We all dislike World of Warcraft's weekly maintenance though we know it is necessary. It's almost a given that Diablo 3 will also have some form of regular maintenance. Why? Because you can't run gaming servers continuously without a minimum of downtime.
So what, many of you will say. Well, here's a scenario. It so happens that you get time off from work/school/etc right on the day when the game is being maintained. You've been itching to play D3 and now you can't, because the servers are offline. Bugger! This has happened to me on more than one occasion with WoW.
2) Some people are in the military and/or deployed overseas where they don't have access to the internet or the connection is spotty and they can't play games which require an internet connection. Sucks to be them, right? Too bad that some of them are HUGE Diablo fans. They'll just have to suck it up and wait until they get back home, in a few months/years. And if they have to redeploy, fuck'em, right?
3) Some people who are working long hours and/or have kids and thus not a lot of time on their hands, might get a little bit of time for themselves every now and then, only to find out that the game is under maintenance or their internet connection is out.
4) Here's a big one that's been bothering me lately: character names. What do I mean by this? Well, we all know that in WoW, character names are unique. I haven't seen anyone so far talk about how character names will be handled, considering that Diablo 3 can only be played online. I highly doubt Blizzard will allow duplicate names. This means that players won't be able to pick their favorite names. Damn it! It would have so worked if the game had an offline single-player mode!
I'm not saying that Diablo 3 should be offline only. No, I'm cool with the online multiplayer aspect of it. But I do realize that many people will miss LAN play and I think it's really sad that Blizzard decided not to include it. However, the inclusion of single player offline mode can be done easily and completely separate from the online mode. It's simple: keep offline characters on your computer, totally segregated from Bnet characters. Wouldn't it be nice to have more satisfied customers?