Warren Buffett's teaching “If you don't feel like owning stocks for 10 years...”

(some excerpts)

Buffett has stocks that it has held for decades, like American Express, and there are many stocks that have been sold in 1 or 2 years. Why is that?
Buffett's reason is simple. If you don't think you're going to buy that stock today, you don't need to hold that stock today.
No matter what the original decision was. Changing an expedient decision may feel like a “loss,” but don't make the situation worse by continuing to take on debts you've created.
This is because by doing so, you'll miss out on opportunities to turn a bad situation around.