We certainly don't want to add complexity without necessity.  But that
is not the reason to avoid "countZero".

In general, if your Smalltalk program knows whether the lowest index
of a collection is 1 or 0 then there is probably something wrong with
it.  Use enumeration protocol.  Say do: and collect: instead of
whileTrue:.  If you need to iterate over the index of a collection,
use keysAndValuesDo:

I bet that in a typical month of Smalltalk programming, I don't ever
need to know whether arrays are indexed starting from 1 or 0.  That is
a low-level implementation detail.  Arrays are low-level
implementation details.  Program at a high level!

-Ralph Johnson