A: Understanding the things: It's not clear which things he evinced to
B: Shy behaviour: He said that due to being shy someone does not ask for information which is to be asked for. It may be possible that he is not shy but before some August personalities, he might get shy of asking for necessary information. It may or may not be harmful to him in the long run. Another option may be that he may collect all the necessary information from him through someone else.
C: Thinking too much about others: It's mainly related to someone who is infatuated for someone because of his/her attractive personality/qualities. It's commonly seen in stupid lovers.
D: Underestimating good person: It may be attributed to someone who is either immature or blindfolded or brainwashed for some other person and is subject to him/her he is doing this mistake.
I think many of us have these types of weaknesses, at least, each of us shares one weakness.
Knowledge is power.
Definitely, there are chances we may lose some opportunities because of our weakness. So we should evaluate the opportunities and wok on and see that we will grab the opportunities. In this process, only our weakness will become a hindrance. So we have to take the necessary steps like getting training or learning a new subject will improve our strengths and we will become more strong.
We should never be under the impression that we have a weakness which can't be avoided. Don't get into that mindset. Always there are ways and means to overcome our weaknesses and we can be on a strong foot and can withstand competition from others. The present-day situation is very tough and unless otherwise, you go an extra mile you can't achieve success.
Thoughts exchanged is knowledge gained.