Why is “A” not used for augmented in Chord symbols?

Question

On Wikipedia it says:

Some of the symbols used for chord quality are similar to those used for interval quality:

    m, or min for minor,
    M, maj, or no symbol (see rule 2 below) for major,
    aug for augmented,
    dim for diminished.

In addition, however,

    Δ is sometimes used for major,[a] instead of the standard M, or maj,
    − is sometimes used for minor, instead of the standard m or min,
    +, or aug, is used for augmented (A is not used),
    o, °, dim, is used for diminished (d is not used),
    ø, or Ø is used for half diminished,
    dom is used for dominant.

Is it just tradition or is there a good reason why A and d are not used for augmented and diminished?

Answer 1

M cannot be confused with the letter name of a note, whereas D and A can. The + is probably due to the interval (usually 5th) being larger than original by a semitone. That being the case, dim could be -, but that is sometimes used to denote minor , NNS uses it. Why o, not a clue! There isn't even an o in the word!

Answer 2

Others mentioned the possible confusion with note names. And indeed, in some German songbooks (like the 1909 "Zupfgeigenhansel") you might find Cv instead of Cdim (v for vermindert), with v not being in competition with a note name.