I don't see any reason why you should regret, or let it stick really. You can regret, yeah, I won't deny that. Just don't let it linger, it has absolutely no use in your life. It doesn't turn back time so why bother letting it stick around. And no, even if Doge did make me regret (which it didn't), I still wouldn't try to find the "next" Doge. I'd still use my own standards in trying to judge a project. That's what I did with Bitcoin, that's what I'd do with the rest of my big investments.
I can spare a few bucks shit coins though for a little bit of gamble here and there

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Don't get hung up on the past, because it will make us miss opportunities that can come at any time in the future. Regret will not bring back anything, so for me there is no point in regretting too much about what has happened. Unless regret can bring us back to the past, then we can do it, but all that will not happen, right? Compared to thinking about the past that has been missed, it is better to focus on the future by continuing to learn, because when the opportunity comes again, we only need to execute it. Opportunities will always be in this space, depending on whether we can use them or not.