Mm, for me, I don't think it is necessarily that I give up on a failed idea--it just gets moved to the back of the line.
To face facts, I have so many ideas, scenes, kinks, and other things I'd like to write stories around I don't foresee myself ever having the chance to get to them all. When I'm in the mood for something I'll try and give it a go, and if / when it fails I usually just move on to the next idea that I'm also interested in and give that a try. Then the next one, and so on. I do occasionally look back, something reigniting my interest/passion for something I've tried, but between the idea I got 5 posts into before my partner poofed, and the one I haven't even tried yet, I often find myself more interested in going on the hunt for the latter.
Plus, I don't want to wear myself out on any one idea and work it into the ground until I'm bored of it, helps keeps things fresh for me to bounce around. And since I usually leave available past ideas, it isn't like I'd be opposed to someone asking about it. ... I also find it helpful to have a variety of ideas so you can better obfuscate your one-trick poni-ness. x3