Candidates can navigate the balance between quality and quantity in study materials for the UPSC exam by selectively curating resources that cover essential concepts comprehensively. It's crucial to prioritize quality materials, such as NCERT textbooks, standard reference books, and reputable online sources, over a larger quantity of mediocre resources. Setting a study schedule that includes focused learning sessions, revising limited quality materials strategically, and regularly testing comprehension can help maintain a balance. This approach ensures depth of understanding while preventing overwhelm from excessive study materials.