Most  of the time estimation where under estimated.

When a resource is missing, you must get it from project runnning late to let yours finishing on time.

One piece is missing.

When running project, you must remain focused on your topic and avoid

distraction from other teams. Silo Principles.

Project team shall monitor other project surrounding. 

Running project does not exclude cooperation with other teams.

Resources are rare

and must be kept preciously. It might be useful later on.