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Buy a coin and hold like you intended but take profits when the coin shoot up like double Profit up to 2x and buy back when the coin dumps, crypto is like a circle, there will be pumps and there will be dumps, in that process of taking profits and buying back you will end up wining both ways, whatever happens you won't entirely lose out.
Think about it
Lol, this is so easy to say. If this was really easy, you should be rich by now. Are you rich? There are flaws over here. Let us say you invested in a coin and then the price drops, never to reach the point of price when you first invested. You won't be making the profit. This is what happens.
Your case is true if you are willing to hold it for long term profit. But you will have to way for years to reach your goal and then wait again for the price to drop.