I simply think Gurren Lagann was badly made. It was trying to be silly, then serious, then silly, then serious, and not only did the jumps destroy all hope of it ever being achieved, I think that it could have done things better in things as basic as drawing-style and voice-acting. Mind you, I watched it subbed, I never watch anime dubbed.
I think Fate/Stay Night had a really really good concept. I loved the whole games thing, and that you summon spirits from forgotten worlds to fight for you. But where it died for me where that I think [I]all[/I] the characters in the anime was horribly made, with the exception of Saber, The King of Conquers (I can't remember his name, you know who I'm talking about. Thor) and the monk guy that looked like the guy from Cowboy Bebop. I personally think its whole way of telling the story was way off. It tried, but it failed - Too many characters introduced at too little time, and every scene with them feels rushed.
Madoka, I admit, I didn't give a fair chance. I tried to fight myself through it three times, but after only getting to episode 4-5 three times I simply gave up. Nothing at all in it caught my interests, I think the story was boring and the characters too try-hard. The only thing I really liked was the art.
I realize I just heavily burned so many peoples waifu's, and for that I apologize, but if you clicked the spoiler, so you signed up for my subjective opinion.
"To improve is to change. To perfect is to change often."
Y'all are lucky I don't namechange here or I'd be going by a different name every two weeks.