You can remember your failures yourself. You don't need to store them somewhere like they are old cars you can pull the alternator off of. Ideas are really hard to come up with. But remember this. You need to be building solutions to problems. Not the other way around.
You will come up with something good eventually. But this is not it. Let it go. Put it on the Product Graveyard.
I'm with you. Im over here still chugging away at the same idea. Meanwhile so many others are slamming out 4 MVPs a month, and most of them are nonsense.