Controls not showing the value you choose after submitting

A quick one before I forget to post about it - common issue when developing a web control (mostly EditorParts these days, or web parts that do not have an ASCX) is that the user chooses values for the text boxes and dropdownd and other controls, click the submit button, but the value in the function that deals with the button click (or the ApplyChanges function in an editorpart) doesnt get the value the user chose. Instead, the value is the old value.
There are several possible things that can cause this (I covered some in a previous article about common mistakes) but one that is so obviously simple that I forget to make sure of is this:
Make sure "base.CreateChildControls();" is the first thing called in the "CreateChildControls" function.
If that doesnt work, read my previous article about the web part life cycle.