The core idea
High-yield bonds often behave more like equities than government bonds because their prices are strongly influenced by corporate earnings, default risk and investor risk appetite.
What is happening underneath
When economic prospects worsen, their credit spreads can widen enough to overwhelm any benefit from falling government yields.
How investors should read it
They remain bonds contractually, but their dominant market risk can be credit rather than duration.
The same market move can carry different information depending on which maturity, issuer and risk premium is changing. Read the question together with the underlying concepts rather than treating one price move as a universal signal.