It's very true that a long term holder sees things totally different from a short term holder, because anytime the market deep, a long term holder sees it as opportunity to buy aggressively as long as it doesn't affect his emergency funds, while a short term holder always panic and most of them sell, anytime their is a correction in the market, so it's very clear that the reaction of an investor determine if truly he is a long term holder or not.
If a person invests properly and creates a desire to buy DCA regularly, then that person will definitely invest for long term. But those who sell opportunistically and are willing to sell their holdings out of greed are essentially in business. They will never be able to keep calm when they see the high movement of the market, so those who are essentially long-term holders must wait for a few years. And he will keep calm and be prepared to extend his investment for longer. That is the clarity of long-term investing.