Because it's roughly what happens, absent other factors on the ex div day. https://www.investopedia.com/articles/investing/091015/how-dividends-affect-stock-pr

Because it's roughly what happens, absent other factors on the ex div day. https://www.investopedia.com/articles/investing/091015/how-dividends-affect-stock-prices.asp https://www.investopedia.com/articles/investing/091015/how-d... https://finance.zacks.com/stock-price-change-dividend-paid-3571.html https://finance.zacks.com/stock-price-change-dividend-paid-3... It's not 100% true, but it's a fair bit better approximation than the other end of the spectrum which is roughly "dividends create free money out of thin air".