In response to Auntie B. here's a little more.
See, the question then arises, how did they (and who were they who did) decide which numerical value gets assigned to which letter.
While all other Greek shmos were bickering about numbers in the 1-26 range, Ceeificarekopos decided that gamma has the value "infinity." To which Betchacanttopses replied that beta should receive the value "infinity plus one."
The entire hall laughed and proposed another toast.
Then Alcaponektikos spoke up and said, "Alpha is any number you can think of or say and then one more" and spilled some excellent wine all over his toga.
Finally, Zero spoke up and said, "I thought the lowest number went first." And all laughed again and drank some more.
Seventeen hours later they lined up and measured their whatsits and decided that way. No, strike that. I said girth last time.