S2 Muses: Leading Indicators of Project Success

I think one of the industry wide pain point is the continued lack of success of large complex IT projects. Post mortem reports galore, lessons learned plenty, infinite measurement points but the guaranteed success  remains elusive. This makes me ponder what could be a leading indicator of a project success. A lot of the metrics are after the fact analysis like schedule slip, cost overruns, defect rate etc. For me a leading indicator will be pointers that identify critical aspects of the project even before a project is started. Well for example the need for a leader or a project champion. Increasingly in organizations the project champion is stripped of all powers to make some tough decisions or the project champion is constrained by a consensus decision making process. The need for a consensus decision making points to  a lack of well defined vision, goal of the project. Also if a project has a long life cycle it has little chance of complete success. More than likely at the end of the project battle will emerge a wounded tired bloody survivor and not a victorious soldier. Anyway I would like to listen for these leading indicators. For one of them I believe is to establish before the start of the project that there will never be a increase in the budget and /or a change in the timeline once started. The only thing that would happen is a trade-off requirements.