Hi guys I was reading through a ODE book and stumbled on this

$$\frac{dy}{dt}= (3-y)(y-t)$$

Where to book claims that $y=3$ is a equilibrium solution but $y=t$ is not. Can someone explain. How I understood it was that the values that make $\frac{dy}{dt}=0$ are the equilibrium solutions and $t$ clearly does that, so I am confused.