> What is so hard in writing table migration, it is like a few minutes of your time. The company I work for has 10's of TB's of data on most customer systems,

> What is so hard in writing table migration, it is like a few minutes of your time. The company I work for has 10's of TB's of data on most customer systems, and migration is either impossible as they have no place to store it, or too costly in time to move. So while writing the code is not hard, the difficulty (or even possibility) of field upgrades can vastly influence whether or not a feature is considered.