Warren Buffett is a stock picker and he famously said: "Give me a million dollars to manage and I'll guarantee you 50% return per year." What he meant is that with relatively small capital an investor is free to choose any stocks, large or small, because he is able to nimbly enter and exit positions. It's also important not to over-diversify which is the tendency with larger capital. Over-diversification can confuse you, increase your investment cost, add layers of required due diligence, and lead to below-average returns.
