With as impressive of an investing track record as Warren Buffett has achieved, you'd expect his Berkshire Hathaway portfolio would be loaded with great stocks. And you'd be right. The good news is that you don't need a huge amount of cash to buy many of those stocks.

Has Warren Buffett given up on stocks amid overstretched valuations? That’s the big question, as the “Oracle of Omaha” has been a net seller in recent months.

Arguably the world's greatest stock picker isn't picking many stocks these days. Warren Buffett has been a net seller of stocks for eight consecutive quarters. There's a reason Buffett isn't buying many stocks -- and it's the same reason he ranks among the greatest investors of all time.

Warren Buffett is widely considered one of the greatest investors ever because he has delivered excellent returns for a long time. The Oracle of Omaha's investing strategy was effective 10 years ago.