# Boltzmann Transport equation: Is df/dt=o for collisionless only?

$$\frac{\mathrm df}{\mathrm dt} = \left(\frac{\partial f}{\partial t}\right)_\text{force}+\left(\frac{\partial f}{\partial t}\right)_\text{diff}+\left(\frac{\partial f}{\partial t}\right)_\text{coll}$$

where the "force" term is the external force, the "diff" term represents the diffusion of particles, and "coll" is the collision term. Source: https://en.wikipedia.org/wiki/Boltzmann_equation

So shouldn't $\frac{\mathrm df}{\mathrm dt}$ be 0 when it is not just collisionless but also force and diffusion must go to zero too?