Bond prices and yields move in opposite directions. If newer bonds offer higher yields, older lower-yield bonds become less attractive, so their price falls until the return gap is competitive.
Why long duration reacts more
Longer-duration bonds lock in cash flows farther into the future. That means a change in discount rates hits them harder because more of the value sits farther away.
Why investors should care
When yields reset quickly, both bond funds and growth-heavy equities can feel pressure. That does not automatically mean a portfolio is broken, but it does mean the bond market is setting the tone for risk assets.