Honestly, the motivation for raiding should always, first and foremost, be because you enjoy it. If you don't enjoy what you're doing, but you keep doing it in the hope that you'll receive some sort of reward...well, that's called a job. And it's not Blizzard's fault. Nobody should bang their heads against a wall because they believe they have to or are forced to. If you don't enjoy LFR just for the raiding aspect of it, and you've been having bad luck, and you just wanna throw in the towel...go ahead. Really, it's fine. If you don't enjoy doing massive amounts of dailys...you shouldn't do so.
I enjoy the fights, even in LFR. They're still far easier than their normal level counterparts, but there's still a bit of excitement for me. And when I go back in the next week, and don't get Lei Shi's staff with the sha-touched gem socket for the second time in a row, even though that's the only thing I really want or need, even though it looks like 4 or 5 others have it, does it annoy me? Hell yeah, it does. But RNG is RNG. I know that eventually, I will get an upgrade.