Strange system of recording stock purchases

I have found that, when recording a stock purchase,
you must not enter a minus sign in the amount column.

When I _do_ enter a minus sign on a buy transaction it magically changes 
to a sell transaction.

This is unlike all other debit transactions where you enter a minus sign 
to indicate a debit transaction.

It's very confusing and counterintuitive to not enter a minus sign for a 
stock transaction (clearly a debit) but transactions like a check paid 
require the minus sign to indicate it should be treated a debit.

My suggestion is that all transactions should operate the same way.
This means a minus sign if the transaction is a debit and no sign if the 
transaction is a credit.

Am I doing something wrong?

Larry Alkoff