The Quick Design window pops up when a new control is dragged on your form.
You can also rightmouse click on an existing control and select the 'Quick Design ...' item to do maintenance.

The Quick Design window:

         

Quick design significantly reduces the steps to develop your form
The time to do this is reduced from minutes into a few seconds!

And the chance of making mistakes is significantly smaller.
Besides control names we also take care of layout issues, and more ...
High quality at top speed!
Easy creation of a pair of controls
With a minimum effort a pair of controls is created.
Just drop a Label on your form and type its text. That's all!

By default automatically a Label and TextBox are created with the correct control names (applying your preferred convention). The following control (by default a TextBox) can be overridden by any other Control, such as a DateTimePicker.
Accelerator check
When the green check mark is shown, you immediately know that the current accelerator is unique. If the accelerator is already present, an exclamation icon is shown. Its tooltip contains a message showing all other controls with the same accelerator.
Required entry
If the input is mandatory, you can make it a required entry. At runtime a message is shown and the corresponding control is selected, so the user can immediately type some text.

You can make your own message or skip the message completely. For a professional feedback message, the '%s' in the message can be used to mention the prompt of the control. The prompt of a control is automatically set for you by the layout engine and can be used for any custom prompt action.
Click here for more information about prompts.
Valid expression
 The user input must meet this expression. You can supply your own expression or select an existing one from the list, such as an "email address" and "numbers only". At runtime a message is shown when the expression is not met and the corresponding control is selected, so the user can immediately type some text.

Like the required entry message, you can make your own message or skip the message completely. And also '%s' can be used in the message to provide professional feedback with the prompt name automatically included.
MaxLength
For TextBoxes it is handy to set the maximum length of text.
By default Visual Studio sets this value to 32767.
Using the Quick Design window, the default is set to 30.
You can set your own preferred default value in the form layout settings.
Control names
The control names are automatically composed for you when typing in the text entry. Your own preferred naming convention is applied here. Of course there are always custom situations when you want to apply another name, so you can override the names here.
 Click here for more information about control naming convention.

Extremely fast creation
For extremely fast creation of your form, there is the option to insert the next control immediately after you pressed OK.
The Quick Design window stays open and allows you to enter the next text at once!
So you only have to enter a range of texts!
Example: to create 8 controls for input of Name, Address, Zipcode and City you only have to:
  1. drag a Label on your form, type in 'Name', check 'Insert again' (press enter);
  2. type 'Address' (press enter);
  3. type 'Zipcode' (press enter);
  4. type 'City', uncheck 'Insert again' CheckBox (press enter) and ready your are!

This can be applied anywhere on your form.
Handy for creating a column of controls.

Easy maintenance
Changing names and text properties is easy! Just type a new text in the Quick Design window and the names of the corresponding controls are changed too.

Always consistent control names! Handy when you made a typing error.
And your layout is ready at once (the text can effect the column width).