In my opinion, no one knows when bitcoin will go up or down, unless someone asks to increase the price or lower the price, therefore it is best to keep checking the price of bitcoin every day, because seeing the growth of bitcoin with your own eyes is much better.
it is true that many predict the price of bitcoin but most of them are wrong so don't be too easy to believe in predictions if there is no clear source so I totally agree with you that no one knows when the price of bitcoin goes up or down if someone is right, it's just a guess.
Bitcoin be a speculative assets made it more difficult to know it price per time, this has been in existence from inception. Although there are experts in this ecosystem that truly understand the technology but still be able to tell the exact figure of Bitcoin up and Downs at a particular time. Basically, bitcoin price in future will be determine by demands when global adoption set inn.