# Cost Overrun Causative Factors in Road Infrastructure Projects: A Frequency and Importance Analysis
## 3 Results and Discussion
### Qualitative Analysis
#### 3.3.1 Qualitative Analysis by Factor
Thus, in the most critical situations, it could generate interruption or affectations to construction activities, which to be mitigated would imply unforeseen activities that may lead to the cost overrun phenomenon. With the same frequency of the 'political situation' factor, the 'legal issues' factor is the seventh most frequently reported. Due to their characteristics, road projects are largely dependent on legal issues, which may affect the continuity of the different stages of the project lifecycle. Legal aspects related to environment, land acquisition, technical regulations, claims and disputes, technical controls, use of public resources, among others, they may involve significant economic investments to be addressed. Therefore, when not properly estimated, the investments can lead to the cost overrun phenomenon. With the same frequency of the 'political situation' and 'legal issues' factors, the 'inadequate bidding method' factor is the seventh most frequently reported. In road projects, the bidding method and associated issues are crucial to ensure success in the construction process development. Some government entities, in the search to minimize costs, use bidding methods based on the selection of the contractor that offers the lowest cost. As a result, contractors participating in the selection process attempt to minimize cost estimates to obtain a greater chance of being selected; situation that leads to cost underestimations, which usually manifest themselves as cost overruns in the construction process development. With the same frequency of 'political situation', 'legal issues', and 'inadequate bidding method' factors, the 'poor site management and supervision' factor is the seventh most frequently reported. It because the management and supervision activities carried out by the contractor during the construction process significantly affect the project cost development. Therefore, proper resource management on the site can minimize costs; on the contrary, management and supervision failures can cause unforeseen costs, which in the case of road projects could become significant cost overruns. An example is the management and supervision of machinery, which due to its characteristics are widely used in road projects, thus, adequate practices improve the construction activities efficiency, promoting the reduction of time, cost and resources associated, on the contrary, poor management and supervision could generate unforeseen costs that could lead to the cost overrun phenomenon. Table 5 shows the cost overrun factors most frequently (top-10) reported in the 18 documents analyzed (Table 3). In addition, Table 5 shows the number of documents that report each factor according to the 45 documents shown in Table 2. The results show that the behavior of the frequency ranks (shown in Table 4) agrees with the number of documents trend that report each factor. Thus, the 'failures in design' factor with Rank = 1 is the most reported in the documents collected that address the issue of cost overruns factors in road projects (Table 2). Therefore, it is evident that the sample of the 18 documents selected is representative of the 45 documents shown in Table 2. \begin{table}
\begin{tabular}{c c c} \hline \hline \multirow{2}{*}{**Frequency Rank (\(\textit{n}\) = 18)**} & \multirow{2}{*}{**Factors**} & **Number of Documents that** \\  & & **Report the Factor (\(\textit{n}\) = 45)** \\ \hline
1 & Failures in design & 35 \\
2 & Price variation of materials & 30 \\
3 & Inadequate project planning & 29 \\
3 & Project scope changes & 26 \\
5 & Design changes & 25 \\
5 & Unrealistic contract duration & 17 \\
7 & Inadequate bidding method & 25 \\
7 & Poor site management and supervision & 23 \\
7 & Political situation & 18 \\
7 & Legal issues & 18 \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Top-10 cost overrun factors and number of documents that report the factor.