Google rolled back the blogger service to a pre-maintenance state and placed the service into read-only mode while the company worked through the problem, making it impossible to post to blogger.

In the pre-Web days, thick client application models were based on widgets, events and event handlers which often resulted in complex event chains which lead to maintenance nightmares.

If you have several release environments, you can practice maintenance on a pre-production environment to minimize risk during a production deploy.