Based on my personal experience wherein I just try to buy anytime I want, wait for the price to rise but instead of what I am expecting, it keeps going down. There is still a right timing for us to buy. One problem is just how to determine at which exact point is the right timing to buy and sell so it must be included on our research.
By timing is all about catching possible lower prices; yes I agree it should be included by your research and analysis so that you can make your trading a perfect timed one. Because of high volatility of markets, we cannot get the exact prices to buy or sell neither. So, you must go for referring your technical part to make sure that you are getting right price at given moment.
Knowing your target is also important. It may seem that it is very easy to earn big money in trading but it isn't. Time and effort is what we really need to be able to determine how did this trading really works.
We cannot simply determine our target levels but it should be coming from same technical analysis. Because, if you're going by your own and comfort zone target levels then you might need to compromise your profit portions.
When we are depending on only the research and analysis even for booking profits then we can avoid disappointments and later regrets.