To be honest OP, I wouldn't completely fault that guy during that time. Also, remember the guy who purchased two (2) pizzas for thousands of BTCs? I mean of course, we're clowning them today due to the decisions they have made but put yourself into their shoes at that time.

Remember that the very fact of a digital currency existing within the realm of the internet, free from any control, and transactions being posted are just some of the things that are beyond comprehension. The fact that you've received thousands of digital currency that can be converted to something physically (e.g. pizza and $$$) means that you won't be able to exercise this opportunity again.

At the end of the day, while we may judge these people according to the decisions they've made in the past, let's all not kid ourselves. I am very sure that if we are in the same situation as theirs, we would most likely done the same.

This is from the early days of Bitcoin when we were not in Bitcoin or did not know about Bitcoin. An even bigger example than this example is in December 2018 when the price of Bitcoin was below $3300, I bought Bitcoin even though I knew about Bitcoin at that time and I bought Bitcoin and sold it again for a small profit. If I had been able to hold Bitcoin at that time, I would have a great financial support at the current price of Bitcoin.

Now when I think about that time, I only regret it. In fact, since Bitcoin was virtual, there was not much faith in Bitcoin at that time, so I was afraid to hold it. And when Bitcoin was first launched in the market, how could anyone gain faith in Bitcoin? Because at that time Bitcoin was unknown and the first digital currency that no one knew about before. That is why the money that was received immediately at that time was a matter of joy for that time. After facing and seeing all these things, we should not miss the opportunity to hold Bitcoin, at least now.

We can say things like that because we already know what happened with Bitcoin, and we know how successful it has been.

Can you say the same thing if something like a new project has been launched? No you can't because the skepticism is at it's peak, and that's what Bitcoin is during those years. There are still lot of skepticism during it's early years of it saying that it's a scam or whatever negative they can say, and that's because it's a new thing. It's a new currency, and I think it's pretty common for investors to feel like that especially if it's new. Those who trusted Bitcoin throughout the years are the ones that are yielding the most profits right now. Those who choose to hold those Bitcoins that they bought when many are criticizing it are the ones that are making the most money now.

I've been selling Bitcoin ever since I joined a Bitcoin-paid signature campaign, and while I'm holding a portion of it, a huge portion of it is being sold. Do I feel regret? Yes, I feel regret and disappointed with my decisions, but dwelling it for a long time will just make me more depressed and stressed with myself. At the end of the day, the past is the past and I can't control it anymore. What I can control is my future, and what I could with those Bitcoins that I'm getting on a weekly basis.

I think the reason why you shouldn't sell your early is because.

Bitcoin is a digital asset and it's decentralized. where price increase on his own without a single control from any other organization

Bitcoin investment for me is an asset where you invest according to your capacity so that you won't be desperate to sell it on a wrong time.  but having other asset will  not make you to sell your bitcoin on a wrong time.
You investing on bitcoin is not just for fun is a life changing journey which you need too acquire patients self control because there's a reward up front.  

That Greg tweet is legendary, but let's be real. A 5x return from $0.06 to $0.30 probably felt as amazing as buying at $6k and selling at $30k.

It's easy to judge him. The real lesson in here is not to "never sell", but rather to never sell your entire stack. Taking profits to enjoy life is fine, just make sure you keep bitcoin.

Well, as long as you still sell in profits, or you sell because you planned it long ago, then there's no room for regrets. Regrets are only those who sell bitcoin too early that are far from their plan, or those who end up panic selling because they don't understand the high volatility of bitcoin. But let's be clear here, selling is never a bad option, all investors should take time to sell their coins, but they should sell at a reasonable price, or sell when they have seen already good profits to sell.

However, not buying again is already an individual's choice. But if you want to experience bigger profits, buying back will always be the best option. Missed opportunities are not supposed to be missed forever, bitcoin never stops giving us opportunities to buy and stack bitcoin.

Even if some investors sold at profit or they sold at a price they already planned for a long time ago, they will still feel regrets if the price of bitcoin suddenly goes up after they sold. Many of us have been guilty of having these kind of feeling of wishing we waited a little longer so we can benefit from the sharp price increase.

Timing the market accurately is not easy, it is infact risky to time the market instead of having a defined plan and working with the plan.  Those who regret their actions after selling are greedy people. No matter the amount of profits they get, they will still regret if they miss out on more profits.

As for those who sell out of panic, the solution they need is for them to work with a plan. The rule to apply should be to wait till the goal of the plan is reached while acting blind to short term  market movements and paying deaf ears to noise.

Selling bitcoin is not entirely bad, a lot of bitcoin investors decide to sell their bitcoin for profit purposes. But selling early their bitcoin, for me that's cutting short the long-term potentials of bitcoin and miss every opportunity that bitcoin halving could offer. No one wants to invest at a loss, therefore selling too early should be avoided to maximize the potential profits of bitcoin.

One thing is certain, if you want maximum amount of your profits, never sell early, but remain patient all throughout your bitcoin investment journey. The best rewards are always found in the end, as there's no shortcuts to it.

A clear example, and I don't know if you remember, was that many forum members said they would sell when BTC reached $100k. The thing is, BTC surpassed the $100k mark and performed better. While many did sell, those who sold above $125k and are now gradually buying back took full advantage.

But now, knowing that the all-time high was around $126k, the smartest thing to do is buy and accumulate as much BTC as possible, since the market is expecting another big all-time high. When? We don't know, but I'm sure it will happen.

I wonder if their regrets will ever end? I think they will continue as long as they live. It was not a mistake to sell Bitcoin in the past because they were happy to sell it then. Instead of time, the price has increased a lot so there is no point in regretting now. Many of us believe that the price of Bitcoin will increase a lot in the future. When Bitcoin reaches $1 million in the future, how will they be? So you should not worry about the past. Wise people do not think about the past but they like to think about the future. So start accumulating BTC again thinking about the future and just hodl.

No I am not in favor of selling btc at a low price. I believe that bitcoin has good potential in the long term. Now we can't be sure about the future because no one knows the future. But I am optimistic that we can take good profits from bitcoin in the future. So instead of focusing on the current market, plan for the long term.