Wikipedia:Autobiography

Writing autobiographies is discouraged because it is difficult to write a neutral, verifiable autobiography, and there are many pitfalls.

It is said that Zaphod Beeblebrox's birth was marked by earthquakes, tidal waves, tornadoes, firestorms, the explosion of three neighbouring stars, and, shortly afterwards, by the issuing of over six and three quarter million writs for damages from all of the major landowners in his Galactic sector. However, the only person by whom this is said is Beeblebrox himself, and there are several possible theories to explain this.

There are a number of fundamental problems with autobiographies:

Just because you honestly believe you are being neutral doesn't mean you are. Unconscious biases can and do exist, and are a very common cause of the problems with autobiographies—which is why we discourage autobiographies themselves and not just active, deliberate self-promotion. Not only does this affect neutrality but it also affects the verifiability and unoriginal research of the autobiography. One may inadvertently slip things in that one may not think need to be attributable even though they do, due to those very same biases.

The threshold between objectivity and autobiographical puffery is culturally constructed and the measure derives from what we are accustomed to consuming as disinterested journalism. The more truly neutral the source, the more truly diverse the sources, the more truly relevant the information, the less risk of the material presenting a self-aggrandizing impression. The principle of neutrality can be understood from the idea that facts appear impressive only when presented matter-of-factly. Merely using neutral language does not guarantee that the language will sound neutral.

Even if you believe you can synthesize an autobiography based only on verifiable material that is not original research you may still not be able to synthesize it in a completely neutral manner. For example, a recognized authority or prominent figure (or a writer composing on the person's behalf) might list objective summary data indicating such things as the sheer volume of one's published material, or the fact that their work has been translated into numerous languages or performed abroad. True claims expressing mere volume or scope can present a non-neutral impression that is usually recognizable to observers as deliberate self-aggrandizement as opposed to restrained journalism. Likewise, deep biographical detail, such as details of one's religious beliefs, the careers of one's non-notable family members, or the mere fact that one has famous friends may not become relevant until and unless one has gained substantial fame. Avoid writing your own eulogy: as economist John Maynard Keynes pointed out, "In the long run, we're all dead."

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