For Win Forms Label controls, single-line captions can be specified. But what if you want to have a longer caption, or a caption that will change at run time? The AutoSize property helps you size the controls to fit larger or smaller captions.
To make a label control resize dynamically to fit its contents
If AutoSize is set to false, the words specified in the Text property will wrap to the next line if possible, but the control will not grow.
Label Class | Using Labels to Create Access Keys | Label Control