Studying Wing Chun requires patience. Many people just study for one or two years, some might just study for a few months and then stop. This is because they think that Wing Chun is not powerful enough and they want to be able to fight immediately. Yes, you can learn Wing Chun and fight after 6 months but the techniques that you have might be ok overcomes somebody weaker than you in class but when you come across as strong and aggressive opponent outside it might not be enough. If we want to reach a high level, we need to learn how to be soft so that we can read our opponent’s energy and strike them when they cannot defend themselves. This takes a long time to develop, but once you reach that level you can use it effortlessly even when you are old. Another thing to remember is that your training journey should be a healthy first and not injure or your training partners. Therefore we save our power, whether it is punching or kicking, until we use it on the Wooden Dummy Muhk Yàhn Jōng 木人樁, even then if we strike hard with our hands or legs then eventually we will injure ourselves. Wing Chun training uses wall punch bag in order to make our fists strong, but we should not use them too much otherwise we will injure ourselves.
We can fight after a short period of training, but to reach a high level where you can use less energy takes many years so you need to be patient and trust the skill.