Bioshock
Borderlands
Dragon's Dogma

Any MMORPG that requires a lot of grinding (world of war craft and such). Always a boring start, but becomes very exciting when you advance and find friends

I feel like Kingdom Hearts 2 is a classic example of a slow start. Playing through Traverse Town with Roxas again was such a slows and painful start. By the time I got through it, I kinda lost interest in the game.

Agreed, 7 is pretty slow. I'm into 8 more with pretty much everything though tbh. 

Kind of a weirder one to point out but the newer Harvest Moon/ Story of Seasons have had that hard to get through introduction segments before you really have much freedom to do anything. I started playing Story of Seasons recently and it almost took me 4 hours before I got past the tutorial and even then, there was extra stuff I had to sit through and accomplish before I was let loose. Weirder with New Beginning since the slow start is just the fact that you have to build the town back up so there's little to do and no townsfolk to interact with at the start, though I found it harder to enjoy myself because it took more work to even get people in your town. The games get more fun after that initial roadblock, but they did irk me when I played them. Probably why I got way more into Stardew Valley since they just set you free right away.

Wind Waker grinds to a halt once you get off Outset and until you get to Dragon Roost Island. I dropped the game a few times as a kid because of Foresaken Fortress, not really a good way to start the game. But once you get past it, it's awesome.

Pokemon Sun and Moon

I gave up on Xenoblade Chronicles and Xenoblade X within the first few hours because I got really bored with them. I've heard they get really good after that, but I just don't have the patience to sink hours into a game I'm not enjoying.

Agree with this too. I loved S/M, but the hand-holding and restrictiveness until you get to the third island detracted from the experience.

I don't think it having much "gravity" to it is a reason to call it slow. Very quickly, you're already exploring, fighting and solving puzzles, just as you do in the rest of the game. You could argue after leaving Kokiri Forest, it's kind of slow, but the actual beginning of the game is in no way slow.

Xenoblade starts at the battle of Sword Valley. Hardly what I'd call a slow beginning.