When it comes to the question of personal identity, we may be using labels to describe ourselves. The flaw of identifying with a label is if somebody else also identifies with the same label, but in their case it means something different, then the use of the label for self-identification becomes inaccurate in meaning.
Therefore, to understand one's personal identity, the use of labels is insufficient in describing who you are.
If one identifies, for example, by their national identity, it can lead to misunderstandings as to who you are from yourself or from others. This is because different individuals can have different ideas or concepts of what this national identity means. For example, for some people, someone who identifies as “Israeli” may mean a very good thing or even an ally in their eyes, while for others the label of “Israeli” may mean enemy or other ideas like people that cut in line and people whose form of talking is yelling. I would also argue that national identity is meaningless when it comes to who you are, both because the deeds of the country itself does not mean your own personal deeds as well as the fact that a nation has so many citizens who are different individuals that the use of national identity as a descriptive term becomes meaningless in the understanding of who you are.
Other labels that one might use to identify themselves with such as “smart” or “funny” can carry different meanings from one individual to another. Even if the meaning is slightly different from one person to another, the use of the label for self-identification becomes inaccurate for the understanding of who you are. For example, the term “smart” by itself does not accurately describe at what skill set or skill level.
Therefore, self-identification using your full name and knowing who you are based on what you do, what you did in the past, and your personal preferences, allows for the complete understanding of who you are.