Not every idea is great. Few will last for more than a moment. For this reason I don't write them down, save for a few exceptional circumstances. Instead, I wait. Good thoughts tend to stick around and great thoughts tend to be all-consuming.
Rather than saving every idea as it arrives, my strategy has been to let these thoughts free, expecting the best ones to return. Often I'll expect this “boomerang effect” to happen more than once, enabling me to better gauge the quality of a given idea and the motivation I have to pursue it. This strategy has also given me more time and freedom to construct those thoughts as I find putting ink to paper has a sort of finality to it that codifies this thought, disincentivizing further change.
From this strategy, I've produced:
And many more.