Minimum scale factor for the shapes in vector graphical applications

There are two scenarios when scaling shapes in graphical applications:

1. The application always keeps the original values of the shape including all of the changes applied on it. In this situation, there is no matter how much the minimum scale factor should be. At any time, the original values can be used to change the shape.
2. The application uses the latest shape values for each change. Obviously, when you scale the shape and set the scale factor to 0 (horizontally and/or vertically), the shape width and/or height will be changed to 0 too. So, if you try to apply another changes on the shape (e.g. try to rescale it to a bigger shape), the width and/or height of the will not be changed as they are now 0 and multiplication of them to any scale factor will be 0 too.
   In this scenario, you should consider a minimum scale factor to prevent disappearing the shape.