Reflective essay

Write a reflective essay. Do you think a particular methodology is more effective and valid than other methodologies (There are many types of social research methods, including surveys, interviews, focus groups, document analysis, ethnography, data mining, experimental (control and experimental groups), network analysis, etc)? For example, are surveys more valid than interviews? Are numbers more valid than observations? Is case study analysis more effective and valid than focus groups? Should the methods always depend on the research proposition?