This is always happening. But the interesting thing is that when in the bullish era, there are also daily traders that will take profits every time they are going to do. So, this is also the reason why people commonly keep rising up in certain periods. I know that big amount of Bitcoin that is sold at once will influence the market to be not stable because of the need for the supply and demand imbalance, so this will cause dropped prices or market corrections. that is why what we need to do is to take the right time to sell our coins, whether it is based on some steps or all in selling. However, never think that this condition will be worse because we are too worried, the Bitcoin market will be always facing a bullish era although it is probably not a really long time to see this.
There's always going to be daily traders that want to get more fiat (or Bitcoin) by moving back and forth. In reality the vast majority of them end up with less money in the end. Specially since they have to pay exchange fees and capital gains taxes, plus the time needed to track all that.
The thing is that you can consider all these movements as short term noise. They don't really impact the long term purchasing power of Bitcoin. That's determined by the fundamentals of it, and those haven't changed since genesis.