## 3 Results and Discussion
### Benefits and Limitations of Lean Tools in Design
#### 3.3.2 Benefits and Limitations of Last Planner System
The key advantages highlighted by experts are supported by the literature, which defines LPS as a tool that helps design teams reduce uncertainty [90], achieving this through structured planning and constant process monitoring. Additionally, LPS decreases workflow variability [71; 91; 92] due to the continuous control exercised throughout the planning phase. Furthermore, this tool improves the reliability of task scheduling at the weekly level, ensuring firm resource commitments from the last planners and refining tasks to guarantee their completion [71; 92]. However, discrepancies emerged among professionals regarding the supposed limitation of LPS to on-site applications, as not all agree with this restriction. The literature points to a lack of LPS implementation in real design cases, as some designers resist adopting the tool in this phase [86]. This point was debated among professionals, who noted that resistance to change is common, especially when companies do not perceive clear value in the tool during the design phase, as many believe its use is exclusive to the construction phase. 3.3.3. Benefits and Limitations of BIM  
MEP professionals agree that BIM is valuable for preventing errors and improving information management in building projects. However, there are discrepancies regarding BIM's ability to achieve a complete digital twin and its impact on visual communication. Some question whether automation enhances team consistency or significantly saves time, although they acknowledge its capacity to reduce miscoordination between specialties and detect issues early. Architects doubt whether BIM improves team consistency and whether automation represents an effective time-saving solution, as they believe human error remains a constant factor. Nonetheless, they appreciate that BIM allows all team members to work on the same model, reducing miscoordination between specialties, though they emphasize that effective communication remains essential. They also agree that BIM facilitates early detection of clashes, though they admit that not all issues can be identified at this stage, as some tend to arise during construction. Regarding disadvantages, most professionals recognize the challenges associated with the costs and infrastructure required for BIM implementation but highlight that it represents a valuable long-term investment. A key insight is that they do not consider proper 3D model management as a disadvantage, arguing that the presence of a BIM coordinator mitigates this difficulty by ensuring model control and accuracy throughout the process. Real estate professionals largely agree on the advantages of BIM but point out some critical aspects. One of these is that the methodology does not directly improve team consistency, as this depends on each individual's work pace. Additionally, while they appreciate BIM's automation, they warn that it can make detecting and correcting certain errors more difficult, as users may become overly dependent on the software. They note that coordination between specialties is not always achieved, especially if users are not sufficiently proficient with the software. They also identify two areas of conflict. The first is resistance to change, which tends to arise when management or decision-makers do not perceive the value of implementing BIM. However, workers will adopt the methodology if it becomes a company requirement. The second is the notion that an internal BIM team is necessary, which they consider unnecessary, as this service is frequently outsourced today. Structural engineers agree with many of BIM's advantages, which are mentioned in Table 11. They recognize that the tool reduces miscoordination, allows for early clash detection, and is an effective visual resource for communication. However, there are discrepancies regarding whether BIM improves consistency or automatically unifies criteria, and some believe that cost savings depend on the company's level of maturity in using BIM.