Because the curriculum is not good enough. It's way too small, and they have no exposure to the actual material other than 1 semester of theory. And because so

Because the curriculum is not good enough. It's way too small, and they have no exposure to the actual material other than 1 semester of theory. And because some people say they did CS, while in fact they did some related study. No experience = no knowledge. It's not just people who just finished their study.