The average time a Wall Street investor holds a stock has shortened dramatically over the decades. At this point, buying and holding a stock for 10 years is a virtual eternity. But there's a benefit to being a small investor because you can hold for that long and you don't have to worry about anyone breathing down your neck about the performance of the stocks you own.You can buy boring but reliable high-yield stocks like Realty Income (O -0.24%). Or dividend growth stocks with an income payoff that builds o ...