If you go to properties of a button and under layout tab you will see radiobutton: Show always or Conditional.
The first statement setting Show Always radiobutton to false, which automaically enables conditional show. Then next statement put a condition which can never be true (1=2), so the button is not show.
Under UnHideIt macro, I remove the contion 1=2, so button is visible again.
Hope I explained it correctly. Let me know if any more questions.