Short-term thinking
Right NOW is the time to buy & Monday will be the time to sell.
Only if someone wants to contribute to the volatility of the markets.
Another thing: If people can afford to buy (this would be money they don't need, the spare cash just lying around), this is really a very good time to buy, I agree. But then they should hold on to their purchase. For years. Rich people, and whoever would become rich through market investments, almost never sell anything. They wait it out and draw on their dividends.
Buy and sell like you're in a casino? That's not investment. That's nuts.