I presume that the first step of your strategy would be to sell 1/4 of your holding now, since it's already doubled (more than once).
I also presume that you mean, the second time, that you sell 1/4 of the 3/4 you have left.
That strategy works for something like Bitcoin, if you got in near the beginning. It's a really nice strategy for that situation.
But let's say your employer gave you got stock options at $1/share which, at the time they were granted, was exactly the stock price. The stock slowly goes up to $2.50, then slowly falls to below $1.
There are two problems with your strategy in this scenario: First, when has it "doubled"? You were given these options for free, and (on the day they were granted), they are worth zero. As soon as the stock goes to $1.01, they've more than doubled... but you don't want to sell then. (This is also true of Bitcoins that you mined back when that was easy. They were essentially free, so when was the first doubling?)
But if you wait until the stock is worth $2 ("doubling" in another sense), then you only sell once, and only a quarter of your holdings. That's much less gain than you could have made.
Your strategy is a good one for a rocketship like Bitcoin. But you often don't know that you're on that kind of a rocketship until it's doubled several times. If you wait for confirmation that you're on a rocketship, you could miss some much smaller, but still really sweet gains.
What I did when I had the options scenario is essentially your strategy, but with much lower numbers. When the stock went up maybe 25% or 50%, I sold off some of the options. And some more when it went up another 25%. That worked very well for me. But if the stock had been a rocketship, I would have missed out on a lot.
Some of this is bound by the size of the investment. Sub 10,000$ returns are not going to change your life, but when you can start cashing in the equivalent of your annual salary not taking money off the table gets risky.
At that point think of it as a math problem.
Suppose you own a stock that’s never going to issue a dividend, but will do buybacks until eventually the company fails. In such situations you can expect 0-X doublings and a final price of zero.
Now, what strategy works best depends on X, buy and hold is clearly a losing strategy in all situations. Further you don’t know X but you can come up with a reasonable bounds as nothing is going to be worth say 10^30$.
Another approach is to simply constantly sell a fixed percentage each month. That’s very useful if you only have one large investment that does not nessisarily fail, just stop growing exponentially.
I also presume that you mean, the second time, that you sell 1/4 of the 3/4 you have left.
That strategy works for something like Bitcoin, if you got in near the beginning. It's a really nice strategy for that situation.
But let's say your employer gave you got stock options at $1/share which, at the time they were granted, was exactly the stock price. The stock slowly goes up to $2.50, then slowly falls to below $1.
There are two problems with your strategy in this scenario: First, when has it "doubled"? You were given these options for free, and (on the day they were granted), they are worth zero. As soon as the stock goes to $1.01, they've more than doubled... but you don't want to sell then. (This is also true of Bitcoins that you mined back when that was easy. They were essentially free, so when was the first doubling?)
But if you wait until the stock is worth $2 ("doubling" in another sense), then you only sell once, and only a quarter of your holdings. That's much less gain than you could have made.
Your strategy is a good one for a rocketship like Bitcoin. But you often don't know that you're on that kind of a rocketship until it's doubled several times. If you wait for confirmation that you're on a rocketship, you could miss some much smaller, but still really sweet gains.
What I did when I had the options scenario is essentially your strategy, but with much lower numbers. When the stock went up maybe 25% or 50%, I sold off some of the options. And some more when it went up another 25%. That worked very well for me. But if the stock had been a rocketship, I would have missed out on a lot.