Out Of Sequence

Unique Configuration

P6 Out of Sequence Logic

There are two main differences between how the P6 scheduling software and SmartPM identify out-of-sequence logic

1. SmartPM assigns the OOS flag to the successor activity (the “necked” activity) while P6 lists the predecessor activity (the activity that initiated the “necking”). For instance, in the following example, SmartPM finds A1020 as out of sequence while P6 lists A1010
2. P6 does not consider an activity out of sequence if the points of two activities linked by the logic tie type are both started, while SPM does. For instance, in the following example, Activity FS9 has an actual start date that is earlier than the actual finish of its predecessor. SmartPM considers this out of sequence while P6 does not

Out-of-sequence activities in CPM scheduling can lead to scheduling inaccuracies, increased risks, challenges in resource management, and difficulties in tracking project progress. To maintain an effective and accurate project schedule, it is essential to adhere to the logical sequencing of activities, as defined in the CPM logic diagram. Properly defined dependencies between tasks help ensure that the project's schedule reflects the most accurate and realistic representation of how work should be executed.

• Disruption of Logical Flow: CPM scheduling is based on the logical sequencing of activities, where each task depends on the completion of its predecessors. Out-of-sequence activities disrupt this logical flow and can create confusion and misalignment in project execution.
• Inaccurate Schedule Analysis: Out-of-sequence activities can lead to inaccuracies in schedule analysis. When activities are not executed in the intended sequence, it becomes challenging to assess the critical path, calculate float, and accurately analyze schedule risks and constraints.
• Increased Schedule Risk: Activities performed out of sequence can introduce risks and uncertainties. Deviating from the planned sequence may result in delays, increased rework, and difficulties in resource allocation and coordination.
• Resource Allocation Challenges: Out-of-sequence activities may require additional resources or may not use resources efficiently, which can lead to resource conflicts and overallocation.
• Reduced Accountability: When activities are executed out of sequence, it can be challenging to hold team members accountable for the correct order and timing of their work. This may lead to misunderstandings and difficulties in managing responsibilities.
• Difficulty in Monitoring Progress: Accurate progress tracking is essential for effective project management. Out-of-sequence activities can make it difficult to monitor and assess the status of tasks, as they may not follow the planned timeline.
• Impaired Risk Management: Accurate CPM schedules are critical for identifying and managing project risks. Out-of-sequence activities can impede risk assessment, making it difficult to anticipate the impact of changes or disruptions on the project schedule.
• Complexity in Execution: Performing activities out of sequence may introduce complexity and potential confusion for the project team. The need for constant coordination and adjustments can disrupt the workflow and hinder efficiency.