Poor example

What's the go with this example? The example must be about the `Control.HandleCreated` event and not about how one does show a message box in an event handler.
There has to be a better explanation about the actual event, how often and under what circumstances it occurs.

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#### Document Details

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* ID: 7b925df9-665a-7094-1735-2a2116f9e8c3
* Version Independent ID: b9a25b86-5633-cc4c-e43e-7ac6f53bea63
* Content: [Control.HandleCreated Event (System.Windows.Forms)](https://docs.microsoft.com/en-us/dotnet/api/system.windows.forms.control.handlecreated?view=netframework-4.7.2)
* Content Source: [xml/System.Windows.Forms/Control.xml](https://github.com/dotnet/dotnet-api-docs/blob/master/xml/System.Windows.Forms/Control.xml)
* Product: **dotnet-api**
* GitHub Login: @dotnet-bot
* Microsoft Alias: **dotnetcontent**