Bitcoin prices sometimes soars so high due to certain matter like speech from a figure.
or
It just sometimes soars without any issue.
Which is the frequent factor? or maybe not both?
You're absolutely right. Sometimes, there are just random movements within the market that people try to attribute to certain events that have virtually no correlation with the price hike/dump. In that sense, there is a lot of noise within the market, especially in the short run, that have a substantial effect on price movement.
For instance, a whale could simply be deciding one day that he wants to load up on a position, and his buys could influence others within the market to take on a similar position.
There is nothing that is predictable about that, nor should it be attributed to bitcoin news of that particular day.
But there are certain news, such as regulations, especially in big crypto countries like China that USED TO have a much bigger impact on the wider markets. However, with the markets now more mature, I doubt that the effect will be as pronounced if there were to be further restrictions on regulation.