Phalcon model column mapping, all or nothing. why?

[hyosang82]

Using database model (Phalcon\Mvc\Model) phalcon 3.4.
Database column names has underscore, and converts it to camelcase using columnMap().

there was no problem... but.

After added new column on table, application did not works normal.
columnMap() must describes all columns on table, or application die.

But there is no problem with column adding when not using columnMap().

A first purpose of web applications, is response normally.
New column added without mapping, it may just warning with normal response.

Why this like so?