The average workday can be so full of operational and project tasks that the PM is simply inundated and may be stuck in a “reactive” mode where he is only able to react to things happening around him rather than taking a proactive approach to nip problems in the bud.
Whenever such a situation threatens to take place with you, one of the approaches can be to simply stop whatever you are currently doing, then take a step back and reassess the situation and the predicament you are in. In warfare tactics, this is known as a “strategic retreat” where some ground is given up to the enemy in order to regroup your resources, reassess the situation and redeploy resources in a more effective manner. By doing this, you may be able to find that some of the tasks that you were heavily involved in may not be that important in the larger context of things or can even be handed over to another party who is in a better position to take on the task!
However, what if you are indeed in an unfortunate situation where all the tasks are of high priority and cannot be handled by any one other than yourself? In this case, you will probably have to raise a few flags and cut your losses by informing the stakeholders that the task pipeline is full and project triage will have to be enforced so that only those tasks that are highly valued by the stakeholders will remain in the pipeline.