If It Doesn’t Work, Move On
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If whatever it is that you tried doesn’t work, don’t dwell on it.
Try something different.
Experiment more.
Approach it from a different perspective.
Pursue something else.
Redefine your goals.
Wishing things would have turned out differently, that you had a bit more luck, or a better strategy is not helpful. Move on and focus on the next bit instead.