I am a value investor, an investment philosophy that boils down to investing in undervalued, under-researched and unpopular companies. Reasons for one of these three elements can differ. Some examples: special situations (e.g. a spin-off or turnaround), analyst coverage (e.g. low coverage or very negative coverage), investor fatigue (e.g. due to earnings misses), market cap (e.g. under the institutional level for market cap), misunderstood parts of the business (e.g. holdings companies), or cyclicals (e.g. sell-side often doesn't manage to look through the cycle).
When markets soar, the following year the sometimes stumble.