If you create a stored procedure that uses defaults for parameters, and a user issues the stored procedure, but misspells the parameter name, SAP ASE executes the stored procedure using the default value and does not issue an error message.
create procedure test @x int = 1 as select @x
It returns the following:
exec test @x = 2 go ---------------- 2
exec test @z = 4 go ----------- 1 (1 row affected) (return status = 0)