Hello forum 👋🏻.  Hope we're all doing good. Okay, let's talk about the so called "4 years cycle".

For starters, I believe in the four years cycle, and that's probably because I'm a trader. Traders do often tend to look for patterns and structures in assets movements, and although some members will say that's just an illusion or a myth, they actually do work.
You know what a hypothesis is, right? They are unproven theories, but after subjecting those hypothesis through numerous tests and experiments and see it holding up and playing out with regards to the hypothesis, then it becomes a real working theory.
In trading, the minimum for acceptance is 3; guess what, we've got 4 proven tests, so right now in my eyes and in the eyes of so many traders out there, the four years cycle is no longer a hypothesis.

But that's not what I want to talk about, I want to talk about:

1) The mechanism behind the four years cycle.
2) The economic implications of this mechanism.
3) How this mechanism influences the four years cycle.
4) The conclusion.

1. The mechanism behind the four years cycle :
The four years cycle is anchored around the miners' reward halving which is triggered at every 210,000 blocks. This event is estimated to occur every 4 years. Now what does this tell us? This event creates bitcoin scarcity coupled with its fixed supply of 21million coins, this makes bitcoin a highly disinflationary currency.

Now you might be asking what does this have to do with anything, well this brings us to my next point of discussion.

2. The economic implications of this mechanism :
We all know the law of supply and demand, right? And how scarcity is a driving force behind the abrupt increase in price of an asset. So yeah, the above mentioned mechanism increases demand naturally. But it still doesn't explain the four years cycle; you're right, but just hear me out a little.

Since we can estimate when this event will take place, traders are positioning themselves for it. This is what truly happens.

3. How this mechanism influences the four years cycle :
When the halving takes place, naturally demand will increase and the price will shoot up (well not linearly but naturally with Higher-Highs and Higher-Lows). It will continue until the market becomes over-saturated and eventually price begins to drop (this is a normal phenomenon for all tradeable assets, no price goes up or down infinitely). Now while dropping, traders keep selling to a point where they decide to wait for or place a buy order in a presumed floor price which most estimates to be at the previous ATH because that seems to be the immediate support, and even if to goes beyond that, it won't be much lower than that price.

These buys (bullish trend) don't happen immediately or exactly at the point of halving, wise traders start accumulating little by little over a 12 - 18 months period pending the event, positioning themselves before the big event so when it is time they'll be in so much profit. And then the process is repeated over and over again.

Now we will say why after the halving, we do see price still going low? That's for two reasons;

1) Short term investors (paper hand) are taking profit.
2) What you're seeing is a normal chart movement of break and retest: price is reversing its trend, so it normally goes back to retest a previous resistance price turning it to support thus confirming the trend reversal movement.

Now, some will say, these are all false, macro-economical news are the real driving forces. Don't worry, let's address this in the conclusion.

4. The conclusion :
There have been news that triggered each market trend like the creation of silk road, Mt. Gox collapse etc. But there have been news within that period that failed to reverse the trend, like in the case of silk road, after FBI shut down, it still continued to rally, the shutdown of miners in China didn't change the trend either. During the 2022 bear market triggered by Terra luna collapse, even with El Salvador adoption, the trend still didn't reverse.

Even when the FTT scandal happened in 2022 that drove price below its previous ATH, this would have triggered an either prolonged or a more aggressive bear market, but instead a bull market resumed after 2 months in anticipation of the halving.

There have been a lot of instances where major news that should've triggered a trend reversal didn't. After months of bear market, we see a bull market being carried over until the halving and beyond. These early bull markets are just smart investors positioning themselves before the event so as to maximize profit because the price at which the halving is triggered will eventually be a strong floor price (not absolute floor price) since most miners won't want to sell below or even on that price, they'd rather sell above it and investors are more than willing to buy above it due to its scarcity.

That's why I said from the get go, the cycle is anchored around the halving. That mechanism triggers a reaction in investors that influences the demand and supply curve of Bitcoin, and since the mechanism is periodically within a specific time frame, the supply and demand curve happens in the same way in a cycle-like manner.