Excellent asnwer that puts the usefulness and imense value of triagulation to the point! I often have students who present triangulation as a way of falsifying or justifying their findingds e.g if certain informants have said something that contradicts what others have said - and in a way judging what is correct and not. And that is obviously NOT the case! You could also go back to original reference from Denzin who coined the term in: Denzin, N.K. 1989. The Research Act, 3rd ed. Englewood Cliffs, NJ, Prentice Hall.
Triangulation is the combination of two or more data sources or the use of more than one approach to the investigation of a research question within the same study in order to increase the credibility and validity of the results. These combinations result in data triangulation, investigator triangulation, methodological triangulation, theoretical triangulation, or analytical triangulation. The intent of using triangulation is to decrease, negate, or counterbalance the deficiency of a single strategy, thereby increasing the ability to interpret the findings. Four different types of triangulation by Denzin
1. Data triangulation, which entails gathering data through several sampling strategies, so that slices of data at different times and social situations, as well as on a variety of people, are gathered.
2. Investigator triangulation, which refers to the use of more than one researcher in the field to gather and interpret data.
3. Theoretical triangulation, which refers to the use of more than one theoretical position in interpreting data
4. Methodological triangulation, which refers to the use of more than one method for gathering data.
When more than one type of triangulation is used, for example, two or more data sources along with two or more investigators, the resulting complex triangulation is referred to as multiple triangulation.
the term triangulation has been wrongly used by many students.
Triangulation facilitates validation of data through cross verification from more than two sources. Triangulation is not just about validation but about deepening and widening one’s understanding in a given area of interest.