Bruce Lee was rejected from the school because he made a fool of many elder students who were acting like they were better but then hardly trained. He was a bit of an ass and pissed off some of Yip Man's other students they then went to him and tried to have him removed. Regardless of that Yip refused but later it was said they gave him a reason. I was told that they told him if he didn't they would stop paying him. Im not sure how true any of this is but what I have been told is that Yip had a gambling issue and was not good with money so his students took care of that. I have also heard Bruce Lee's mother had German ancestry and this was one other reason Yip dismissed him. Supposedly Yip didn't much care but had little choice and according to William Cheung was told to continue to train him. If any of this is correct Bruce realized Cheung was very good but didn't know that Yip had showed him anything secret. Bruce knew what he was taught was not as good as it should be and he then started learning other things. He then came up with JKD from what I remember he was a bit upset because he wanted people to adapt to their own needs but many wanted to learn his fighting method and started to emulate him. If Cheung is telling the truth he has said Bruce was planning to visit before his death and Cheung was going to tell him about his private lessons with Yip. This is in his book: My Life With Wing Chun Pg62.