Why are informal methods used more often than formal amendment process?

Answer 1

The formal amendment process was made to be difficult, if the amendment process was easy, the Constitution would not be held in such high regard, which i essential to political stability.  The informal process is easier and quicker.  It does not really amend the Constitution, only a formal amendment can. However, the meaning of the Constitution, or the interpretation, can change with the times. The changing interpretation is the informal amendment.