Like other Microsoft software, Visio likes to help sometimes and it may differ from your undersanding of the word. One common way of helping is to create new pages automatically for you if you get too close to the margins.

As map makers, you want your drawings to be close to the margins but without making new pages.

To turn this feature off:

• Switch the Design tab.
• Find the Auto Size button on the left side of the ribbon.
• Click the button. It is a toggle, so it will turn back on if you prefer it to be enabled.