## 3 Results
### Discussion and Insights  
To understand the main differences between the current and future scenarios, an overall comparison of both scenarios is presented in Table 8.  
Thus, through the comparison of both scenarios, there are critical aspects to highlight. Even though the proposed heuristic did not allow to have better or worst results, when compared to the routes developed by the worker of the company, the proposed heuristic meets the following set of characteristics:  
* It allows affecting customers to teams without compromising the competence of the team to serve the affected customer;
* All routes obtained through the heuristic are possible and achievable;
* It allowed affecting all customers to teams, without leaving any customer left to serve;
* All teams' constraints have been respected;
* The use of zip codes as the criteria for selecting the next customer to include in the route may not be the best criteria to improve the distances traveled between customers. Regardless, these criteria can be used;All time windows were respected, and this should have resulted in no reschedules of teams;
* The number of clients each team served was consistently affected, thus resulting in routes that did not serve a high number of customers nor a low number of customers. Only three teams have a higher number of clients to serve when compared to the others.  
This study evidences the use of a heuristic as an alternative to support the route-creating process of a company whose focus is on the delivery and assembly of furniture providing insights into the literature regarding DIRP. As already highlighted by [21; 39], this study supports the literature about the use of heuristics as a tool that generally yields near-optimal solutions which can efficiently deal with a large set of constraints and still produce near-optimal solutions. The results indicate that the proposed heuristic can affect customers to teams without compromising the team's skills and competencies to serve the customers and respecting all constraints, including time windows. Thus corroborating [37; 38; 41; 55] emphasized the use of heuristics for solving VRPTWs in real-world situations. Moreover, through the use of performance indicators, this study developed and compared two scenarios (using the current manual method for route construction vs. the use of a heuristic) to assess the value of DIRP as a new delivery method [5].  
Some major aspects of our findings are related to the process of developing a heuristic to support the route-creating process for the delivery and assembly of furniture and include:  
* It is critical to understand how routes are developed since this process allows to define the predominant criteria used to create routes;
* There is a need to monitor the planning process to create routes. In this way, it is possible to understand how the workers responsible for this task operate and how they organize and affect different customers into teams;
* There is a need to carefully define the main objectives to achieve the proposed heuristic and to define decision variables and restrictions, as it is crucial to understand how to make decisions and the boundaries of the problem;
* General rules, as priority rules, are important to be defined, and all rules need to be clearly defined. Additionally, rules for unpredictable situations need to be defined;
* Finally, it is important to test the proposed heuristic through performance indicators to understand if it is adequate for the problem.