$BTC $ETH Crypto markets are subject to frequent fluctuations as they generally have high volatility. Periods of market decline can depend on several main factors:

1. **Regulation News:** Regulatory moves or statements by governments and financial authorities regarding cryptocurrencies can create uncertainty among investors and lead to selling pressure.

2. **Macroeconomic Factors:** Macroeconomic factors such as global economic recession, inflation rates, interest rate increases may reduce the interest in cryptocurrencies, which are seen as risky assets.

3. **Market Manipulation:** Sudden and large purchases or sales by large investors (whales) can cause sudden price movements in the market.

4. **Technological or Security Issues:** Hacking incidents or security breaches in crypto exchanges may cause loss of trust in the market in general.

5. **Investor Sentiment:** The overall sentiment and perception in the market also plays a big role. Panic selling or profit taking can trigger declines.

Some points that investors should pay attention to during downturns:

- **Not to Panic:** It may be important not to panic sell in sudden declines and to stick to the long-term strategy.

- **Doing Research:** It may be useful to have detailed information about the reasons for the decline and to conduct market analysis.

- **Risk Management:** Implementing diversification and risk management strategies can help minimize potential losses.

As a result, crypto markets are inherently volatile, causing declines and rises to occur frequently. Making careful and informed investment decisions is important to creating a more solid investment strategy over the long term.