I don't think that this is still valid in the ever faster changing world. How many of the biggest succes stories on the stock exchange are companies that did not exist 20 years ago? Facebook, Twitter, Snapchat, Whatsapp, Paypal, Amazon, Google... One century ago you could start a business and continue for 100 years selling the same things. Today life cycle of products are much shorter, so lifecycle of companies too. And if they cannot quickly adapt to changing markets they don't survive. if you buy stocks of these losing companies...to hold...
I'm not putting forward investment as a strategy suggestion, I'm simply seeking to illuminate the difference between true investors and all the rest, I'm not saying its a good policy, for all I know maybe it never was. It just might - conceivably - be a decent strategy if you have millions to start off with (I've never even considered what would be a good financial plan if I was that rich, its unlikely to happen) and decades of life ahead. But no doubt some millionaire ET member will come along and tell us its a terrible strategy compared to others, I don't argue with that. What I find distasteful is the financial industry's lie that an investor can have a 3 year investment time horizon - that's a trader.