Lay investors often do not know when or how much to invest in large, mid-, or small-cap funds. If they invest only in large-cap schemes and small and mid-cap stocks rally, as often happens in the market, they will miss out on the gains. Lay investors often do not know when or how much to invest in large, mid-, or small-cap funds. If they invest only in large-cap schemes and small and mid-cap stocks rally, as often happens in the market, they will miss out on the gains. Economic Times