Honestly, I'm more impressed at the shows I finished, rather than gave up on. I gave up on Hill Street Blues in the 80s because I no longer had access to a TV. I gave up on Happy Days, Laverne and Shirley, Little House on the Prairie, Taxi (which I regret), I Dream of Jeanie, Bewitched, The Jeffersons and many more over the years. However, I finished The Brady Bunch (really), MASH, the Muppet Show, Newhart, Lost (unfortunately), Avatar: The Last Airbender, The West Wing, The Gilmore Girls, and many more. I'm pretty sure I've given up on more than I finished.
The Returned (English)-- I think I'll try the original version, sounds like people liked that better
Once Upon a Time-- Got bored after the first season, gave up after the second.
Jane the Virgin-- After five episodes, I think I get the idea. Cute, but I have no confidence it will go anywhere interesting.
24-- I just couldn't deal with the torture, and by the middle of the third season, it was clear that it would be a larger part of the series.
Bones-- I watched five seasons, mostly for my wife.
Curb Your Enthusiasm-- It was funny for a couple seasons, and then the humor grew stale for me.
The Simpsons-- Haven't we all given up on this?
Daredevil-- The first season was okay, but I couldn't get into the second.