If you know how to value businesses, it's crazy to own 50 stocks or 40 stocks or 30 stocks, probably because there aren't that many wonderful businesses understandable to a single human being in all likelihood. To forego buying more of some super-wonderful business and instead put your money into #30 or #35 on your list of attractiveness just strikes Charlie and me as madness.
The best business returns are usually achieved by companies that are doing something quite similar today to what they were doing five or ten years ago.
One of the ironies of the stock market is the emphasis on activity. Brokers, using terms such as 'marketability' and 'liquidity,' sing the praises of companies with high share turnover... but investors should understand that what is good for the croupier is not good for the customer. A hyperactive stock market is the pick pocket of enterprise.
The ideal business is one that earns very high returns on capital and that keeps using lots of capital at those high returns. That becomes a compounding machine.
If you own a wonderful business...the best thing to do is keep it. All you're going to do is trade your wonderful business for a whole bunch of cash, which isn't as good as the business, and you got the problem of investing in other businesses, and you probably paid a tax in between. So my advice to anybody who owns a wonderful business is keep it.