## 3 Results and Analysis
### Deviation Magnitudes by Causes of Deficiency  
Relevant information content in Appendices A and B about analyzed projects is needed for this section. Appendix A consists of a table that contains technical information for the 25 projects analyzed. The ID column represents the contract number as registered in SECOP I or SECOP II. Additional columns include type, contracting entity, planned cost, real cost, cost variation, planned duration, real duration, and time schedule variation. Appendix B consists of a table presenting the relationship between the causes found for each project. Table 5 shows the average percentages of schedule deviations (SD) and cost deviations (CD) for projects affected and unaffected by the most frequently occurring planning deficiencies identified in the analyzed projects. First, the lack of experience of the planner (C\({}_{10}\)) was identified in 15 road intersection projects, resulting in an average increase of 128% in project duration and 26.2% in initial cost for the affected projects. To identify this cause, a thorough review of the initial project documentation was conducted, revealing that the contractor requested a review shortly after the contract award. This led to significant design changes and the inclusion of unforeseen but necessary activities. Unaffected projects exhibited smaller variations, highlighting the considerable influence of this cause. Second, deficient estimation of material quantities (C\({}_{6}\)) caused more significant average variations in schedule and cost than the previous cause, with 136% and 27.9%, respectively. Although this cause affects fewer projects, its impact is more substantial, as evidenced by the comparison between affected and unaffected projects. This cause relates to the need for more planner experience, as both are present in most analyzed projects. The third identified cause is the omission of road markings in planning (C\({}_{16}\)). Analysis of project budgets revealed that projects with strict control over signage exhibited lower variations in schedule and cost, with an increase of 151.8% in schedule and 23.9% in cost compared to the first two causes. Projects unaffected by this cause showed smaller average variations. Finally, the omission or deficiency in the definition of work packages (WBS) (C\({}_{13}\)) was identified by analyzing incidents during the construction phase. Affected projects commonly added unforeseen activities, necessitating meetings to approve them and define their costs. These projects experienced average variations of 122.4% in time and 30.1% in cost. These four main causes show a considerable difference in magnitude between affected and unaffected projects. Therefore, Table 5 highlights the cases where a direct relationship was identified between the average variations of affected and unaffected projects for each cause with a \"*\". The fifth identified cause, deficient coordination with public utilities (water, sanitary, electrical, and other surface or subway networks) (C\({}_{3}\)), affected fewer projects. The analysis of project documents revealed a need for more information gathering on existing networks. During the construction phase, unforeseen networks were encountered, leading to deviations in schedule and cost. The sixth identified cause, inadequate exploration of existing