Visual Basic Concepts
When you first place a new control instance on a form or other container, Visual Basic chooses a property to highlight the Properties window. This will be the same as the last property that was highlighted, if the new control has that property. Otherwise, Visual Basic uses the property marked as the user interface default.
If you don't specify this user interface default, Visual Basic highlights a property according to various internal criteria, such as the order in which you added properties to the type library.
To specify the user interface default for your control
Tip The best candidate for the user interface default is the property users will most often set. For example, the Interval property is the user interface default for the Timer control.