New Delhi, Aug. 11 -- Markets have a curious habit. When a story is popular, investors often want more of it, even after prices have risen sharply. When a sector or company runs into trouble, the instinct is usually the opposite: sell first and ask questions later.

Contrarian investing begins in that uncomfortable space between the two. At its heart, the contrarian style is about examining what the market has stopped liking. It looks at an unpopular company or sector and asks a simple question: has the price fallen because the business has fundamentally weakened, or because expectations and sentiment have become too negative?

This is not the same as buying everything that looks cheap. Some stocks are inexpensive for good reason. Their c...