You don't need much analysis before you start investing in bitcoin, all just need is to have a basic knowledge and a discretionary Income that you are to invest and focus much on continuously accumulating bitcoin through the dca strategy and hold for two or more bitcoin cycles. But for traders who are into bitcoin for short-term profits they need to analyze the market before they start trading and not investing. Talking about not investing when bitcoin is high simply means you are a trader not an investor and if are using dca strategy you can buy bitcoin at all time so longer as you are an investor you can invest in bitcoin at all times since you are not in for short-term profits.
You can not lose when you buy to hodl Bitcoin which is why I am confused when I hear people say that they lost when they invested in Bitcoin. If you are trading, that is not investing and you can lose when trading but when hodling you can not lose. You will lose when you decide to sell the Bitcoin that you were hodling. As you are holding and Bitcoin has not reach the price that you want to sell, you can keep Hodling untill the price of Bitcoin get to that price that you want to sell. You are not going to lose if you keep hodling regardless of what happens. The only thing that might happen is when you will have to keep hodling while you wait for the market to keep growing and when you are not in a hurry to sell, you will be more determined to keep hodling.