I was hoping we could get a list started on circumstances that UA considers under/not under it's control when it comes to delays, cancellations and the misconnects they cause.

For example, I know that mechanical delays are treated as the airline's fault, but that weather is not.

What about things like Crew Scheduling, Ramp Service, ATC, Customer Service Handling, Baggage Handling and others you can think of that are listed on UA's "Reason" when you look up Flight Status online?