Games you didn't initially like, but you did after you gave them a second go

The first Witcher. I hated it at first (around 2008 when I first played it) but the second time I gave it a shot I went through the boring prologue and loved it right after that. I'm glad I gave it a second chance.

Can't remember any more off the top of my head.

Half Life 1.
Portal 1.
POSTAL 2.

I agree with Skyrim, Dragon Age and Witcher
still need to give a second try to Dragon Age and Witcher though...
Unturned was good for a week

• Blocks That Matter.
  Didn't like it at first, so I stopped playing. Came back a couple of months later and I actually quite enjoyed it.

• Edna & Harvey: Harvey's New Eyes
  Not exactly what you're asking for but kind of: I had seen a let's play of it and found it extremely stupid. A few months later I got the chance to play it myself, and I actually enjoyed it very much :D

Other than that I can't think of another game right now.

bad rats
( ͡^ ͜ʖ ͡^)

Insurgency for me. Just kept dying over and over again the first time so ragequit. Returned to it a little while ago and ended up playing almost every night.

Dark Souls 1 - I got really frustrated the first time i tried it. But after watching some lets plays, i got really into it. It´s a great game if you understand the mechanics.

The Witcher 3

MEtro 2033. When i played first time, I was irritated by the firing of the weapon, it realized there are not very good, but I gave a second chance for game, and then could not stop until the end

Borderlands 2

I'm gonna copy-paste (part of) my previous post from another thread.

La-Mulana: in fact, when I first played the original freeware release, I was unable to get into it at all. I gave it a second chance and this time it really grew on me, so much that I paid full price for the remake when it appeared on GOG.

Brütal Legend and Mafia.

rage

Binding of Isaac, didn't think much of it at first but when I dug a bit deeper I couldn't stop playing.
And still playing Rebirth.

GTAIV
The binding of isaac (still can't stand SMB)
Hotline Miami 2

XCOM: Enemy Unknown. Didn't like the changes they've made and thought the original was way better in pretty much every aspect.
Still gotta finish my first playthrough, but I'm loving it!

Lollipop Chainsaw - I wasn't digging the combat at first, it does a pretty poor job of explaining most everything, and the main character takes a bit getting used to. But once I got the combat figured out, figured out how to heal, and embraced Suda51's weirdness, I really enjoyed it. I'd like to see it come to PC eventually. I think a lot of people would get a kick out of it.

SKYRIM !

LoL was that game OP, i know the feeling.

In the past i was wondering why people like a click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click-click game. I end up playing it when my best man suggested it to me (he is not yet but will be in 2 months :D).

Now? I am Gold V :D and have over 30 skins

Portal, Borderlands, Killing Floor... Had them all since 2009-2010 and played each probably about an hour before quitting. Revisited 2 or 3 years later and think they're all great games. :)

I actually gave Dirt 3 a second chance recently and ended up liking it a lot more. I also decided to give GRID another go and am liking it even more, though I haven't had a chance to formulate my thoughts on it yet. World of Guns was another game I needed a second try to get into.

The first Red Orchestra. Very unforgiving, hard to master, make me feel i was a sucker at FPS game, which i'm not (generally i'm doing pretty good). I hated it because i couldn't survive, was killed a lot, killing none at most. Then i managed to get the game right, starting to play it better. Took some time, but then, i liked the game.

Agreed with DAO. I left it unplayed for months after finishing the first quest and now I'm 140+ hs into DAI :D

Dead Island - I started to play with friends from the beginning. They were skilled,were skipping dialogues,were fighting well and were getting last achievements. I lost sense of game, thought it's bored. Then I played alone Riptide, I liked and came back to first part. My tip: never start playing new game with skilled friends, but I can't say that you won't have fun. But you can lose motivation to play without them.

1. Mark Of The Ninja
2. Counter-Strike: Global Offensive
3. Dead Space
4. Sid Meier's Civilization V
5. Deus Ex: Human Revolution
6. Fortix

There are probably more, but I can't recall any at the moment.